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Prefixes

A Dictionary of Prefixes
About Prefixes and Suffixes
Affixes (which for English means prefixes and suffixes ) are very common; infixes occur in some languages, such as Arabic. Affixes are particularly common in academic texts so is is worth spending a little time to become familiar with their use and meaning, especially if English is not your first language. As an indication of how common they are, almost every example sentence in this list contains various other examples of affixes apart from the one highlighted. For example:
astro-
of the stars astronomy, astronomical, astronomer, astrology, astronaut, astrologer, astrological, astrophysics "Astronomers have been working to better understand the galactic environments of fast radio bursts (FRBs) – intense, momentary bursts of energy occurring in mere milliseconds and with unknown cosmic origins." (Glowacki 2023)

Astronomers is the highlighted example but there are others:
working, galactic, environments, momentary, milliseconds, unknown, cosmic.


prefix-
meaning of the prefix examples of words using this prefix examples or comments regarding this prefix
 
a-
lacking, missing something asymmetry, atypical, asynchronous, asymmetric, asexual "The distributions of male and female students between subject areas remain asymmetrical." (Parr 2015)
astro-
of the stars astronomy, astronomical, astronomer, astrology, astronaut, astrologer, astrological, astrophysics "Astronomers have been working to better understand the galactic environments of fast radio bursts (FRBs) – intense, momentary bursts of energy occurring in mere milliseconds and with unknown cosmic origins." (Glowacki 2023)
aer(o)-
of the air aerospace, aeroplane, aerodynamic, aerodynamics, aero-engines, aerial, aerobics, aerobic, aerosol, aerodrome, aerobatic, aeronautics, aeration, aeronautical, aerobically "You’ll need take an aeronautical knowledge test every two years and possess an “operator’s certificate” for the specific UAS aircraft you are flying." (Rapp 2015)
agri-
concerned with farming agriculture, agriculturalist, agricultural, agrichemical, agrichemically, agribusiness " Farmers can maintain or increase biodiversity in agricultural landscapes by planting their crops in smaller fields." (Fahrig 2020)
ambi-
two, both, double ambidextrous, ambiguity, ambiguous, ambivalent, ambivalence, ambiguously "We found those with positive attitudes towards ambiguity were more creative, better leaders and better overall performers." (Becker and O’Connor 2019)
ante-
before, in front of antenatal, ante-room, antechamber, anterior, antecedents, antediluvian "Drive-through “fever clinics,” common in 2009, were the antecedents to the drive-through COVID-19 test sites now opening throughout the country." (Clendenin 2020)
anti-
against, opposed to antislavery, anti-semitism, anti-social, anti-government, antiseptic, anti-aircraft, anti-communist, anti-fascist, anti-racist, anti-apartheid, anti-war, anti-terrorist, anti-nuclear, anti-racism, anti-inflammatory, anti-competitive, anti-climax, anti-inflation, ant-clockwise, antibody, antibiotics, antithesis, antidote, antipathy, antithetical "More than 13% of U.S. adults take an antidepressant medication for depression or for other reasons." (Patterson and Kayser 2023)
arch-
highest, to the highest degree, worst archbishop, archdeacons, arch-enemy, arch-rivals, arch-conservative, arch-villain
audio-
of sound, hearing audiovisual, audiometric, audiology "In a time when the audiovisual is our primary mode of communication, the archive as an institution protecting and championing our shared history is more important than ever." (Duckett 2020)
auto-
self autobiography, automobile, autobiographical, automotive, autopilot, automatically, automatic, autonomy, autonomous, automated, automation, autocratic, autocracy, autonomously "Universities across the world are considering whether to start automatically recording lectures." (Crook 2015)
be-
to cause to be befriend, bewitch, belittle, bedevil, befit, befuddle, beguile, besmirch, bequeath "Webster’s neighbors accused her of witchcraft in 1683, when she was around 60 years old, claiming she worked with the devil to bewitch local livestock." (Marshall 2019)
bi-
two bilingual, bicycles, bisexual, bicentenary, biplane, bi-monthly, bidirectional, bipartisan, bilaterally, bi-annual, bipedal, bi-weekly, binoculars, bifurcation, bisected "It’s estimated that half the world’s population is bilingual, and two-thirds of the world’s children grow up in an environment where several languages intersect." (Aparicio 2021)
bio-
living, of life biological, biology, biography, biochemical, biotechnology, biologists, biographer, biomass, biodiversity, biomedical, biosphere, biodegradable, biogas, biochemists, biofuels, biomechanical, biophysics "Biodiversity conservation and the careful management of natural resources are key issues today in international relations." (Ivkovich and Grichik 2022)
centi-
a hundred, a hundredth century, centipede, centilitre, centimetre "By the late 20th century, reviews of climate science held stark warnings about the path the world was on as humans continued to burn fossil fuels." (Dee 2022)
co-
together, with, joint co-operation, co-operative, co-ordination, co-operate, co-ordinated, coincided, co-ordinator, correspondent, correspondence, collaboration, coherent, collision, correlated, collaborative, coherence, coefficient, correspondingly, coexist "It teaches co-operation, and the skills to run co-operative organisations." (Patmore 2022)
contra-
against, opposed to contraception, contraceptive, contrariwise, contraindicated, contraindications, contra-flow, contrast, contradiction, contradictory, contradict, contravene, contravention "Chaos Theory is a delicious contradiction - a science of predicting the behaviour of “inherently unpredictable” systems." (Borwein (Jon) and Rose 2012)
counter-
against, opposite, opposed to counteract, counter-productive, counter-attack, counterclaim, counter-revolutionary, counterbalance, counter-culture, counter-revolution, counterweight, counter-insurgency, counter-argument, counter-offensive, counter-offer, counter-intelligence, counter-measures, counterparts "But we also revealed that with the right balance of time spent exercising and moving, it may be possible to counteract the negatives of sitting." (Diaz and Chastin 2021)
cross- (1)
against crossbar, crossbow, crosswind
cross- (2)
being part of two or more groups, mixing, mixed cross-border, crossbreed, crosscheck, cross-contamination, cross-fertilization, cross-reference, crossroads, cross-training "This cross-fertilization of ideas and methods led to breakthroughs ranging from using DNA to store computer data to creating 3D “DNA origami” structures." (Maynard 2022)
cyber-
related to computers or computingcyber-attack, cybercrime, cybernetics, cyberspace, cyberterrorism "In the past financial year, the Australian Cyber Security Centre received 76,000 cyber-crime reports – on average, one every seven minutes." (Jeong and Doss 2022)
de-
to reverse an action decomposed, dehydrated, detoxification, decode, debugging. deregulated, demobilisation, destabilization, destabilizing, deforestation "If you don’t consume enough water, you may experience symptoms of dehydration such as headaches, dizziness, tiredness, low concentration, constipation and a dry mouth." (Burch and Ball 2022)
di-
two dioxide, dipole, dimorphism, diversity, diverse, diode "The alarming rate of carbon dioxide flowing into our atmosphere is affecting plant life in interesting ways – but perhaps not in the way you’d expect." (Smith et al. 2020)
dia-
across, through diameter, diagonal, diagonally, diaphragm, dialogue, diametrically "Most remarkably, it spread out almost concentrically over a distance of about 130km from the volcano, creating a plume with a 260km diameter, before it was distorted by the wind." (Cronin 2022)
dis-
lack of, the opposite of, not disorder, disability, disadvantages, disagreement, disagree, disappearance, disbelief, disliked, dissatisfaction, disadvantaged, disapproval, disregard, dissatisfied, disarmament, disqualified "The hype around the Bermuda Triangle can be traced back to a series of unexplained disappearances of ships and aircraft." (Satterley 2020)
e-
electronic, relating to the Internet email, e-commerce, e-learning
eco-
concerning the environment, ecologyeco-friendly, ecotourism, ecosystem, eco-warrior"It’s clear that supporting children to care for the natural world from a young age is vital if we are to build an eco-friendly future." (Hosany 2022)
en- (1)
forms a verb concerning containment enclose, encase, encircle, entomb, entrap, enwrap, envelop "Indonesia was able to enclose its archipelago by drawing a special line known as an “archipelagic baseline”." (Liliansa 2023)
en- (2)
forms a verb concerning cause, cause to be - enable, enchant, encode, encourage, endanger, enfeeble, engrave, enhance, enlighten, enrage, enrapture, enslave, entangle, enthral "This increase in job satisfaction could potentially encourage teachers to stay in the profession longer, thereby reducing turnover and potentially saving school districts hundreds of thousands of dollars." (Martinez 2023)
equi-
same, equal equivalent, equivalence, equilateral, equidistant, equilibrium, equitable, equivocal, equitably "One tonne of nitrous oxide is equivalent to 298 tonnes of carbon dioxide." (Barton and Grace 2014)
ex-
former, previous ex-wife, ex-husband, ex-soviet, ex-servicemen, ex-service, ex- army, ex-soldier, ex-president, ex-girlfriend, ex-employee, ex-boyfriend, ex-minister, ex-king, ex-chairman
extra-
outside, beyond, very extraordinary, extraordinarily, extracellular, extra-mural, extra-curricular, extra-marital, extraterrestrial, extra-time, extrajudicial, extra-sensory, extradition, extrapolation, extraneous, extrapolate "Many visitors to Arnhem Land in the Northern Territory are struck by the magnificent cliffs, stunning bird life and extraordinary rock art." (Nayinggul et al. 2023)
fore-
before, in front of foreground, foresee, forearm, foresight, forestall, forefathers, forewarned, foreshore, foretaste, forecast, forehead, forefront, forefinger, forerunner, forecourt, foreword, forebears, foreboding, foregone, foreshadowed "Because of its small number, the Javan rhino population is particularly vulnerable to stochastic or random natural events, which are difficult to foresee and control." (Sunarto 2021)
geo-
of the earth geography, geographical, geological, geology, geologist, geographer, geophysical, geomorphology, geothermal, geochemical, geometric, geometry "But in a new analysis of 220 years of political data, we show that deep cultural connections between countries such as shared linguistic or religious ancestry matter more than geography." (Welch et al. 2022)
hyper-
extreme, exaggerated hypertension, hyperactive, hypersensitive, hypersensitivity, hyperactivity, hyperventilation, hyperinflation, hypermarket "When I was a child in the 1980s, the people I knew with attention-deficit/hyperactivity disorder were hyperactive boys who went to the school nurse at lunchtime to get their medicine." (Knouse 2022)
ill-
not suitable, inappropriate, improperill-advised, ill-conceived, ill-considered, ill-defined, ill-fitting, ill-health, ill-mannered, ill-suited "Britain’s ill-advised decision to leave only reinforces the idea that such projects are definitively off the historical agenda." (Beeson 2016)
il-
incorrect, the opposite ofillegal, illegible, illegitimate, illiberal, illicit, illiterate, illogical "The Buried podcast asks why so much of our waste is being disposed of in illegal ways and who exactly is responsible." (Purdy 2023)
im-
incorrect, the opposite ofimbalanced, immaculate, immaterial, immature, immeasurable, immobile, immoderate, immoral, immortal, immovable, immutable, impatient, imperfect, impermissible, impersonal, impiety, implausible, impossible, impotent, impractical, improbable "Popular ideas about teenagers are often polarised: from lazy, immature school kids who love to wake up late, to threatening gangs of youths dressed in hoodies, to reckless children who need to be protected from their own stupid decisions." (Kelly 2018)
in-
the opposite of, not informal, inadequate, insufficient, inappropriate, invisible, incredible, incapable, invalid, incomplete, inability, inequality "Their languages are sometimes viewed as deficient forms of Standard Australian English and can be “invisible” to teachers and education systems." (Steele, Wigglesworth, and Gower 2022)
inter-
between, among international, interaction, interactive, internationally, interact, inter-war, intercity, interrelated, intergovernmental, intersection, interplay, interdependence, interview, interpretation, intervention, interface, interference, intermediate, interval, interim, interpret, intervene, interfere, interruption, interviewer, interrupt, interpreter, interfering, interchange, intermittent "Conversational receptiveness is effective because it makes the interaction less confrontational and therefore less unpleasant." (Minson 2023)
intra-
inside intravenous, intracellular, intravenously, intra-industry, intra-oceanic, intra-regional "Clinical trials for intravenous administration of phages are ongoing." (Mathew 2019)
ir-
the opposite of, not irrational, irreconcilable, irrecoverable, irredeemable, irreducible, irrefutable, irregular, irrelevant, irremediable irreplaceable, irrepressible, irresistible, irresolute, irresponsible, irreversible, irrevocable"These are branched and zigzag on an irregular path towards the earth." (Lowke 2022)
kilo-
a thousand kilobyte, kilogram, kilohertz, kilometre, kiloton, kilowatt
mal-
bad, badly malnutrition, malpractice, maladministration, malfunction, malnourished, malformations, maltreatment "Food insecurity – difficulties getting enough nutritious food for a healthy life – is a growing problem globally. It has been linked to many health and social problems including malnutrition, difficulties managing diabetes, impaired development in childhood, and reduced school performance for children." (Fledderjohann, Owino, and Patterson 2023)
mega-
one million, also extrememegabyte, megahertz, megaton, megawatt, megabucks, megastar, megastore "For example, our eyes take in over one megabyte of data every second." (Cleo 2023)
micro-
very small, one millionthmicro-organism, microbiology, microchip, microclimate, microcomputer, microcosm, microeconomics, microfilm, microfossil, microgram, micrometer, micronutrient, microprocessor, microvolt "In fact, it is known to cause more types of disease than any other single micro-organism." (Good 2023)
mid-
in the middle ofmid-afternoon, mid-1990s, mid-range, mid-summer, mid-way, mid-week, midday, midfield, midnight, midsection, midwinter "The farther north you live, the longer it takes for the amount and intensity of daylight to start significantly increasing in midwinter, since your location is tilting away from the Sun." (Hence 2022)
milli-
one thousandthmilligram, millilitre, millimetre, millisecond"Espresso methods vary but give an average of 10.5 milligrams per gram (mg/g), compared to 9.7–10.2mg/g for most other methods." (Beckett 2022)
mini-
small minibus, mini-bar, minigrams, minicomputer, mini-series, mini-skirt, minicab, minigolf, mini-boom, mini-breaks "Millions of people in Africa’s cities rely on public transport to get around. Minibuses are especially common, whether you’re in Accra, Dar es Salaam, Lagos or Nairobi." (Boateng 2021)
mis-
wrongly, badly misunderstanding, misuse, misfortune, misconduct, misplaced, mistrust, misinterpret, misunderstand "A further misunderstanding is that feedback is something that is done by academics and given to students. These beliefs are deeply held in academic culture." (Henderson 2017)
mono-
one monopoly, monoxide, monotonous, monograph, monolithic, monochrome, monopolistic, monotony, monologue, monogamous, monotone, monogamy, monocle, monotheism, monolingual, monosyllables "Carbon monoxide consists of a carbon and a single oxygen (hence the “mono” in the name and the formula CO)." (Lorch 2022)
multi-
many multimedia, multinational, multiparty, multilateral, multi-million, multidisciplinary, multicultural, multiprocessing, multi-coloured, multi-user, multi-purpose, multi-racial, multi-storey, multi-millionaire, multi-faceted, multilingual, multi-ethnic, multiple, multiply, multitude, multiplier, multiplicity, multiplication "If we invite children to play a part in such stories, we will soon realise that black and white are just two colours in a multi-coloured story world." (Kucirkova 2014)
neo-
new neo-classical, neonatal, neo-nazi, neo-marxist, neo-fascist, neo-gothic, neo-conservative, neoclassicism, neo-colonialism, neo-liberal, neolithic, neophyte, neologism "A large study undertaken in 2013 in the US demonstrated other positive effects for babies who receive music therapy in neonatal units." (Coombes 2019)
non-
not non-profit, nonsense, non-fiction, non-commercial, non-governmental, non-linear, non-existent, nonspecific, non-members, non-resident, non-refundable, non-standard, nonviolent, non-compliance, non-executive, non-stop, non-verbal, non-aligned"Their work-life balance was “less than ideal or non-existent”." (Gobby and Karnovsky 2022)
omni-
every, all omnidirectional, omnipotence, omnipresent, omniscient, omnivore, omnivorous "So an omnivorous diet would have made these people far more resilient than those who relied on big game hunting." (Pettitt 2022)
out-
do better, go beyond outrun, outpace, outwit, outlast, outstrip, outlive, outmanoeuvre, outperform, outgrow, outnumber, outflank "All things will outlast us, the land will change, and survive … Yes, the land will be different. But new things will come of it." (McGrath 2020)
over-
exceed, exaggerate, go beyond overlap, overthrow, overflow, overweight, overdue, overcrowded, overdose, overgrown, overloaded, overjoyed "The term spillover evokes images of a container of liquid overflowing, and this image is a great metaphor for how the process works." (Mayer 2023)
pan-
all, world-wide pan-European, pan-Africanist, pan-Arab, pan-African, pan-American, panorama, panoramic "A 360-degree panoramic tour is available online, allowing visitors an immersive experience of the dioramas." (Browning et al. 2020)
photo-
concerned with photography or light photocell, photochemical, photocopier, photodiode, photoelectric, photograph, photography, photojournalism, photometer, photomontage, photoreceptor, photosensitive, photosynthesis, phototherapy, photovoltaic"Life on Earth owes its existence to photosynthesis – a process which is 2.3 billion years old." (Brinkert 2023)
physio-
of the body physiological, physiology, physiotherapist, physiotherapy, physiologically, physiologist, physiognomy, physiochemical "This communication between food and genes may affect your health, physiology and longevity." (Dus 2022)
poly-
many polygamy, polycarbonate, polysyllabic, polytechnic, polymer, polythene, polystyrene, polygon, polynomial, polymorphism, polyphonic, polyphony, polygonal, polyglot "Instead of aiming to create a single polygon of protected land on a map, this new approach seeks to assemble a large protected area with diverse owners who all benefit from participating." (Jachowski 2023)
post-
after post-war, postgraduate, postmodern, postmodernism, post-industrial, postnatal, post-election, postdoctoral, post-colonial, post-retirement, post-revolutionary, post-glacial, post-tax,postponed, postscript, postponement, posterior, posterity, post-mortem, posthumous, postprandial, postoperative "Campaigns to reuse industrial age buildings and to repurpose railroad corridors as riverfront recreational trails further helped cement Pittsburgh’s new post-industrial identity." (Dieterich-Ward 2017)
pre-
before premature, pre-tax, pre-war, prehistoric, prerequisite, preview, pre-school, pre-existing, presupposition, precondition, pre-election, pre-arranged, pre-recorded, pre-determined, predict, predecessor, preparation, precedent, precautions, preface, preventive, preparatory, prelude, precedence, premise, precursor, presuppose, precede "One of the most puzzling of questions around this prehistoric site has been what those vessels contained." (Tanasi 2018)
pro-
in favour of pro-democracy, pro-active, pro-government, pro-life, pro-independence, pro-western, pro-European, pro-social, pro-choice, pro-nuclear "We need to be pro-active about improving care for women who have had a heart attack and raising awareness about the unique risks women face." (Chow and Brieger 2018)
proto-
first, original prototype, prototypical, proto-fish, protoplasm, protozoan "We then built a physical prototype lattice with adjustable electromechanical springs arranged in a triangular lattice." (Lee 2022)
pseudo-
false, imitation pseudo-scientific, pseudo-science, pseudo-religious, pseudo-history, pseudo-academic, pseudo-intellectual "However, this is a pseudo-scientific myth popularised in the first half of the 20th century by the linguist Benjamin Whorf." (Martínez 2022)
psycho-
of the mind psychological, psychology, psychologist, psychoanalysis, psychologically, psychoanalytic, psychotic, psychosis, psychotherapy, psychosomatic "But whether you are shopping for food, clothes or gadgets, the retailers are using the power of psychological persuasion to influence your decisions – and help you part with your cash." (Jansson-Boyd 2022)
quasi-
partly, similar in certain waysquasi-governmental, quasi-judicial, quasi-religious "It must also have a quasi-judicial unit that can surcharge offenders and determine those that are liable for prosecution." (Bansah 2022)
re-
again, back renewed, review, recycling, rebuilt, repayment, reproduced, reproductive, regeneration, reorganisation, regain, rebuilding, reunion, replay, renew, relocation, renamed, restructure "Organs like our skin (yes, the skin is the biggest organ of the body!) need to regenerate often." (Polo 2020)
retro-
looking to the past, looking back, acting in reverseretroactive, retrofit, retrograde, retrogression, retrospective "This even accounted for their retrograde motion – an illusionary change in the movement of planets through the sky." (Dorrian and Whittaker 2020)
self-
by, for, or of oneself or itselfself-absorbed, self-appointed, self-assertion, self-assurance, self-awareness, self-belief, self-catering, self-confessed, self-confidence, self-conscious, self-contained, self-control, self-critical, self-deception, self-delusion, self-denial, self-deprecation, self-discipline, self-effacement, self-employed, self-esteem, self-evident, self-explanatory, self-expression, self-financing, self-governing, self-help, self-imposed, self-indulgence, self-mockery, self-perpetuating, self-pity, self-possession, self-proclaimed, self-reliance, self-respect, self-restraint, self-righteous, self-rule, self-styled, self-sufficient, self-taught, self-worth, selfishness, selfless "Toddlers also naturally demonstrate their self-awareness by their ability to use and understand self-referential language such as I, me, you and my." (Martin, Ross, and Cunningham 2016)
semi-
half semi-final, semiconductor, semi-detached, semi-skilled, semi-circular, semi-automatic, semi-circle, semi-autonomous, semi-darkness, semitone, semi-finalists, semi-permanent, semi-official, semi-literate, semi-professional, semi-independent, semi-conscious "These are the visual (eyes), vestibular (inner ear and semi-circular canals) and somotosensory (sensation feedback from joints in ankles, knees, spine and neck) systems." (Skelton 2015)
socio-
relating to others or society socio-cultural, socio-economic, socio-political, sociobiology, sociolinguistic, sociological, sociologist "Not surprisingly, these types of challenges are exacerbated for students from low socio-economic backgrounds." (Klinger et al. 2021)
sub-
lower, less than, lower in importance or rank subordinate, subsection, submarine, subconscious, subordination, subset, subdivided, subcommittee, sub-contractors, subterranean, subunits, subway "Even to me, having spent a lifetime researching orchids, the idea of a subterranean orchid is like finding life on Mars." (Clements 2020)
super-
greater, above, better supermarket, supernatural, superimposed, superstar, superego, superstructure, superpower, superstore, superhuman, supercomputer, supersonic, superglue "A chain reaction begins, with new magma fragments exposing fresh hot interior surfaces to water, and the explosions repeat, ultimately jetting out volcanic particles and causing blasts with supersonic speeds." (Cronin 2022)
sur-
over, above surmounted, surpassed, surrealist, surrealism, surreal, surcharge, surpass, surmount, surtax "Not only did sales rise, but they also surpassed CD sales for the first time since 1988, according to a new report from the Recording Industry Association of America." (Zagorsky 2023)
techno-
of applied science technology, technological, technologies, technologically, technologist, technocrat, technocratic "Contrary to popular belief, the original Luddites were not anti-technology, nor were they technologically incompetent." (Maynard 2023)
tele-
distanttelecommunications, telephone, television, teleconference, telemarketing, telepathy "Google and Facebook dominate web search and social media, respectively, in ways that echo the great US monopolies of the past: rail in the 19th century, then oil and later telecommunications in the 20th." (Dwyer 2021)
thermo-
of heat, temperature thermometer, thermostat, thermodynamics, thermonuclear, thermodynamic, thermostatic, thermostatically, thermoplastic "The beginnings of measuring fever go back more than 400 years. At the turn of the 17th century, several scholars dealt with the development of thermometers." (Hollerbach 2021)
trans-
across, from one state to another transformation, transform, transplant, transnational, transplantation, transatlantic, transport, transfer, transaction, transmission, translation, translated, transcription, transit, transitional, transportation, transmit, transcript, transmitter, transfusion, translucent, transparency "We hear the phrase “digital transformation” a lot these days. It’s often used to describe the process of replacing functions and services that were once done face-to-face by human beings with online interactions that are faster, more convenient and “empower” the user." (Techatassanasoontorn et al. 2022)
tri-
three tripod, triennial, tricycle, triplane, tri-partite, triangle, triangular, trinity, triple, trilogy, tripled, triplets, triads, triplicate, triumvirate "We did this training on 200 different lattice structures and found that a triangular lattice was best at achieving all of the shapes we tested." (Lee 2022)
ultra-
beyond, extreme ultraviolet, ultrasound, ultrasonic, ultra-modern, ultra-right, ultra-left, ultra-conservative, ultra-thin, ultra-sensitive, ultralight "Ultrasound can do a whole lot more than create images of unborn babies." (Feeney 2017)
un- (1)
the opposite of, not unemployment, unable, unlikely, unlike, unfortunately, unknown, unlimited, unusual, undoubtedly, uncertain, uncertainty, unexpected, unnecessary, unconscious, unavailable, undefined, unsigned, unhappy, unstable, unfair, uncommon, unemployed, unchanged, unauthorized, uncomfortable, unused, unclear, unwanted, unsuccessful, unpleasant, unlawful, unjust, unprecedented, unacceptable, unrelated, unbiased, unreal, unaware
un- (2)
to reverse an action, to deprive of unveil, uncover, undo, unlock, unsubscribe, unwrap
under- (1)
too little, not enough underestimate, underestimated, undervalued, underdeveloped, underrated, underprivileged, underfunding "Why do men see themselves as so much brighter, while women consistently underestimate their intelligence?" (Reilly 2022)
under- (2)
beneath, lower than underlying, underground, undergraduate, underwear, underline, undergrowth, under-secretary, underclass, underworld, understatement, undertones "This might seem fairly innocuous, but its an argument that has grim implications and is based on a misreading of the underlying causes of the current crises." (Alberro 2020)
uni-
one unilaterally, unicorn, unidirectional, uniprocessor, unilinear, unisex, unipolar, unicellular, unicycle, unidimensional, united, union, unit, unique, unity, universal, uniform, unified, unification, unite, unitary, unison, uniqueness, unify "Toxoplasma is a protozoan, a unicellular being so small that it lives inside animal cells." (Pineda 2023)
vice-
deputy, next in rank vice-president, vice-chairman, vice-captain, vice-chancellor, vice-admiral, vice-premier, vice-marshal, vice-presidential, vice-presidency, vice-principal "Three players, including captain Steve Smith and vice-captain David Warner, received suspensions." (Tiffen 2022)
 

See also the suffixes page.