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The SPECIALIST Lexicon

Prefix List - 2025

This list includes the most common prefixes (a word element that only used as a prefix) and combining forms. Please note that prefixes can be used by itself (prefix), with space (prefix ), or with hyphen (prefix-). For example, prefix of "non" can be added to word significant as:

  • nonsignificant|significant
  • non-significant|significant
  • non significant|significant
The following tables list all prefixes for Lexical Tools derivations:

 PrefixClassSenseNegationExamplePrecisionInstancesOccurrencesExceptionsStatus
1 Afro O relating to Africa O Afro-American 57.14% 21 12 9 2012
2 Anglo O relating to England O Anglo-Irish 51.52% 33 17 16 2012
3 Euro O European O Eurocentric 35.29% 17 6 11 2012
4 Franco O French, France O Francophile 0.00% 6 0 6 2012
5 Indo O relating to the Indian subcontinent O Indo-European 52.38% 21 11 10 2012
6 a B lacking in, lack of, not, without N asexual, asymmetric 26.23% 1365 358 1007 2012
verb > predicative adjective with progressive aspect O afloat, atremble
on, in, at O abed, amidst, ashore
in (such) a state or condition O afresh
in (such) a manner O aloud, alive
7 abs O away, from O abstract 0.00% 15 0 15 2014
8 af O addition or increase O affirm 4.11% 73 3 70 2014
9 allo O other, different O alloimmunity, allosome 53.31% 287 153 134 2020
10 ambi O both O ambitendency 46.67% 30 14 16 2012
11 amphi O two, both, on both sides O amphiaster, amphitheater, amphibian 59.52% 42 25 17 2012
12 an B lacking in, lack of, not, without N anemic 34.74% 308 107 201 2012
up, against O anode
13 ana O up, against O anatoxin 15.74% 108 17 91 2012
14 ante O before O antenatal 55.22% 67 37 30 2012
15 anti N opposite, against N anti-war, antivirus, anti-human 73.93% 7058 5218 1840 2012
16 apo O away, different from O apomorphine 58.67% 196 115 81 2012
detached, separate O apocarpous
formed from, related to O apocodeine
17 arch O supreme, highest, worst O archangel 15.91% 44 7 37 2012
preeminent, extreme O archcapitalist, archinfamy
first in time, primitive O archfather, archform
18 astro O star O astrobiology 41.30% 46 19 27 2012
astrological, astrological and O astrodiagnosis, astromedical
aster in cells O astrosphere
19 at O change into, movememnt to, addition or increase O attend 3.53% 85 3 82 2014
20 auto O self O autobiography, automatic 43.03% 839 361 478 2013
automatic, self-acting, self-regulating O autofeed, autowind
of, by, affecting or for the same individual O autohemagglutination, autovaccine
self-caused, self-induced O autointoxication
acting as an antibody on or produced as an antibody for one’s own antigens O autoagglutinin, autohemolysin
21 be O equipped with, covered with, beset with (pejorative or facetious) O bedeviled, becalm, bedazzle, bewitch 19.55% 220 43 177 2012
to a great degree, thoroughly O becudgel, befuddle, bespatter
about, to, at, upon, against; intransitive verbs from intransitive verbs O bestride, bespeak
make, cause to be, treat as; verbs from adjectives or nouns O belittle, benumb, befriend
chemical prefix of unknown meaning O bekanamycin, bemethyl
22 bi O two O bicycle 43.79% 918 402 516 2012
23 bio O biological O biodegrade 47.88% 1132 542 590 2012
24 bis O both; of or belonging to both; two O bisischiatic, bismarine 71.56% 109 78 31 2014
doubled O bisdimethylamino, bisquaternary
25 cardio O heart; cardiac; heart action O cardiokymography 57.65% 340 196 144 2015
26 circum O around O circumnavigate 58.40% 125 73 52 2012
27 cis O on this side O cis-vaccenate 73.91% 46 34 12 2014
28 co O joint, with, accompanying O co-worker, coordinator, cooperation, cohabit 35.94% 1405 505 900 2012
in or to the same degree O coextensive, coeval
operating together or reciprocally O coterm
of the complement of an angle O cosine, codeclination
29 col O together or with O colleague 8.14% 86 7 79 2012
colon O colectasia
30 com O together or with O commingle 2.58% 194 5 189 2012
31 con O together or with O confederation 11.88% 446 53 393 2012
cone O conus
32 contra N opposite N contradict 37.50% 88 33 55 2012
33 contro N opposite N contralateral, contravert 25.00% 8 2 6 2022
34 cor O together or with O correlation 6.09% 115 7 108 2012
35 counter N against, in opposition to N counteract, counterpart 54.44% 428 233 195 2012
36 cryo O ice O cryogenics 50.74% 337 171 166 2012
37 crypto O hidden, secret O cryptography 62.50% 64 40 24 2012
38 de B reverse action, get rid of, removed, without N de-emphasise 33.27% 2020 672 1348 2012
down O depress
get off of (something) O detrain, deplane
derived or compounded from (something) O deacetyl
having removal of one or more atoms of (a specified element) O dehydro-, deoxy-
39 demi O half O demiembryo, demispan 64.71% 17 11 6 2012
40 demo O people O demography 0.00% 19 0 19 2012
41 deoxy O less oxygen O deoxyribonucleic, deoxycholic 33.21% 271 90 181 2022
42 di O two O dioxide 70.27% 1729 1215 514 2012
43 dif O apart O differ 5.00% 20 1 19 2014
44 dis N not, opposite of N disloyal, disagree 31.49% 794 250 544 2014
reverse action, get rid of N disconnect, disinformation
apart N dissect
45 down O to make something lesser, lower or worse O downgrade 47.13% 244 115 129 2016
46 du O two O duet 1.54% 65 1 64 2013
47 duo O two O duovirus 53.85% 13 7 6 2013
48 dys B abnormal, diseased, bad, unfavorable,faulty N dysplasia, dyspathy, dysfunction 62.79% 258 162 96 2012
difficult, with difficulty O dysmenorrhea, dysoxidize
absence or reverse of O dysteleology
49 eco O ecological O ecosystem 38.46% 91 35 56 2013
50 electro O electric, electricity O electroablation 50.38% 782 394 388 2013
electromagnetic O electrochronograph
electron-related O electrophilic
51 em O to make into, to put into, to get into O empower 19.57% 92 18 74 2013
to provide with O empower
to cause to be (sometimes with suffix –en) O embolden
so as to cover or surround; thoroughly O embower
52 en O to make into, to put into, to get into O enmesh 28.49% 365 104 261 2013
in, within, inside O endermic, enzootic
chemically saturated; having one double bond O enamine
53 epi O upon, at, close upon, in addition O epidermis 47.01% 385 181 204 2013
petrographically altered O epidiorite
epimer of a specified chemical compound O epicholesterol, epirhamnose
chemical compound or group distinguished from another by having a bridge connection O epichlorhydrin
54 ex O former O ex-wife 14.92% 362 54 308 2013
out of O export
55 extra O outside O extracurricular 68.37% 1489 1018 471 2013
56 fore O before O forearm, forerunner 40.86% 186 76 110 2013
at or toward the front; the front part of something O forearm
57 geo O relating to the earth or its surface O geography 50.38% 133 67 66 2013
58 gyro O spinning on an axis O gyrokinetic 33.33% 15 5 10 2013
in a ring or spiral O gyromancy
59 haem O blood O haemagglutinin 33.33% 69 23 46 2014
60 haemo O blood O haemodialysis 47.32% 224 106 118 2014
61 hem O blood O hemagglutinin 20.25% 79 16 63 2014
blood O hemagglutinin
blood O hemagglutinin
62 hemi O half O hemiataxia 57.91% 449 260 189 2013
63 hemo O blood O hemodialysis 47.37% 228 108 120 2014
64 hetero O different O heterosexual 50.79% 380 193 187 2013
isomeric with or closely related to a (specified) compound O heteroxanthine
65 homo O same O homogenous, homologous 54.05% 346 187 159 2013
homologous with a (specified) organic compound O homoserine
from the same species; corresponding in type of structure O homograft, homolysin
66 hydro O relating to water, or using water O hydroelectricity 58.00% 350 203 147 2013
containing hydrogen O hydroborate
characterized by an accumulation of fluid in a (specified) body part O hydronephrosis
hydroid O hydromedusa
67 hyper O above, over O hyperthermia 55.63% 1350 751 599 2013
68 hypo O under or below something, low O hypothermia 58.91% 713 420 293 2014
69 ideo O image, idea O ideograph 35.71% 28 10 18 2014
70 idio O individual, personal, unique O idiographic 34.69% 49 17 32 2014
71 il N not, opposite of N illegal 27.78% 54 15 39 2014
72 im N not, opposite of N immature 21.31% 413 88 325 2014
73 in B in, into O insert 33.46% 1871 626 1245 2014
not, opposite of N inexact
74 infra O below, beneath O infrared 64.53% 516 333 183 2014
75 inter O among, between O intercede, interstate, interact 64.98% 4255 2765 1490 2012
76 intra O inside, within O intravenous 65.62% 3662 2403 1259 2012
77 ir N not, opposite of N irregular 30.52% 154 47 107 2014
78 iso O equal O isochromatic 73.28% 827 606 221 2014
79 macro O long O macrobiotic 56.56% 343 194 149 2014
80 mal O bad(ly) O malfunction 30.29% 175 53 122 2014
81 maxi O very long, very large O maxi-circle 25.00% 16 4 12 2014
82 mega O great, large O megabase 62.50% 160 100 60 2014
83 megalo O great, large O megastar, megalopolis 61.29% 31 19 12 2014
84 meta O after, along with, beyond, among, behind O meta-theory 58.79% 643 378 265 2014
85 micro O small O microautoradiogram 50.86% 2157 1097 1060 2014
86 mid O middle O midlife 51.03% 874 446 428 2014
87 midi O medium-sized O midiplasmin 100.00% 2 2 0 2014
88 mini O small O minibus 58.70% 230 135 95 2014
89 mis N wrong, astray N misinformation, misguide 48.60% 570 277 293 2014
90 mono O sole, only O monogamy 61.38% 857 526 331 2014
91 moto O movement O motoneuron 20.83% 24 5 19 2015
92 multi O many O multi-storey 56.92% 4120 2345 1775 2012
many times over; in many respects O multimillionaire, multispecialist
affecting many parts O multiglandular
93 neo O new O neolithic 52.71% 406 214 192 2014
94 non N not N nonexistent 75.15% 17604 13230 4374 2012
95 ob O blocking, against, concealing O ibstruct 3.77% 53 2 51 2014
96 oc O blocking, against, concealing O occult 0.00% 30 0 30 2014
97 of O blocking, against, concealing O offend 0.00% 7 0 7 2014
98 omni O all O omnipotent, omnipresent 44.00% 25 11 14 2012
99 op O blocking, against, concealing O oppose 1.92% 52 1 51 2014
100 ortho O correcting or straightening O orthodontics, orthotropic 67.18% 195 131 64 2012
indicates a 1,2-substituted benzene ring in organice chemistry O orthonitrophenol
indicates the common form of an acid in inorganic chemistry O orthoboric acid
chemical prefix O orthoformate
101 out O better, faster, longer, beyond O outreach, outcome 20.61% 359 74 285 2012
102 over O too much O overreact, overact 47.83% 1522 728 794 2012
103 oxy O relating to oxygen O oxynitrate, oxyconformity 64.97% 177 115 62 2022
sharp, pointed O oxyhyperglycemia, oxyesthesia
104 paed O child O paedogenetic 0.00% 2 0 2 2014
105 paedo O child O paedogenetic 77.78% 9 7 2 2014
106 paid O child O NONE �% 0 0 0 2013
107 paido O child O NONE �% 0 0 0 2013
108 paleo O old O paleolithic 47.76% 67 32 35 2012
109 pan O all, worldwide O pan-African 51.75% 315 163 152 2012
110 para O beside, beyond O parallel 63.30% 1000 633 367 2012
isomeric with, polymeric with, or otherwise closely related to O paracasein
the relation of two opposite positions in the benzene ring that are separated by two carbon atoms O parasymphysial
a derivative in which two substituting groups occupy such positions O para-xylene
111 ped O foot O pedestrian 6.25% 16 1 15 2012
creature or object having feet or footlike projections O Pediastrum, pedrail
something (specified) involving feet O pedomotor
child O pedogenetic
112 pedo O child O pedogenetic 30.43% 23 7 16 2014
113 per O through, completely, wrongly, exceedingly O permeate, permute 28.96% 297 86 211 2012
in chemistry, to denote a large amount or designate combination of an element in its highest valence O perchloroethylene
114 peri O around O periabdominal 71.66% 1969 1411 558 2012
near O perihelion
enclosing, surrounding O perineurium
tissue surrounding (specified part) O periarthritis
115 photo O light, photography, photograph O photoelectric 66.56% 978 651 327 2012
116 pod O foot O podiatrist 0.00% 16 0 16 2012
117 poly O many O polygon 65.12% 1058 689 369 2012
chemistry--containing more than one and especially more than two or three units of (a specified substance) O polyatomic
chemistry--polymer of, polymerized O polyethylene
chemistry--isopoly- O polymolybdate
118 post O after O post-election, post-graduation, postpone 79.39% 9804 7783 2021 2012
119 pre O before O pre-election, pre-enter, predict 73.45% 10098 7417 2681 2012
120 preter O beyond, past, more than O preternatural 9.09% 11 1 10 2012
121 pro O for, on the side of O pro-life 40.60% 1096 445 651 2013
substitute, deputy O proconsul
before O procambium
122 pros O toward O Prosthesis 15.00% 20 3 17 2012
123 proto O first, original O protoplasm, prototype 57.23% 173 99 74 2012
124 pseudo O false, imitation O pseudonym 62.41% 3517 2195 1322 2012
125 pyr O fire O pyroantimonate 17.24% 29 5 24 2014
in chemistry, indicates a dimeric acid anhydride O pyrophosphoric acid
due to or or attributed to the action of fire or heat O pyrochlore
of fiery color O pyrophanite
fever, fever producing O pyrotoxin
126 pyro O fire O pyroantimonate 52.55% 137 72 65 2012
in chemistry, indicates a dimeric acid anhydride O pyrophosphoric acid
due to or or attributed to the action of fire or heat O pyrochlore
of fiery color O pyrophanite
fever, fever producing O pyrotoxin
127 quasi O partly, almost, appearing to be but not really O quasiaxial 61.16% 345 211 134 2012
128 re O again, back O rerun 36.64% 4645 1702 2943 2012
129 retro O backwards O retrograde 50.26% 382 192 190 2014
130 self O self O self-sufficient 47.92% 866 415 451 2014
131 semi O half O semicircle 51.61% 965 498 467 2014
132 socio O society, social, sociological O sociopath 48.86% 219 107 112 2014
133 step O family relation by remarriage O stepbrother 11.26% 151 17 134 2014
134 sub O below, under O subway 62.38% 4423 2759 1664 2012
135 sup O below, under O support 1.67% 60 1 59 2014
136 super O above, over O supervisor 48.38% 1604 776 828 2014
137 supra O above, over O suprarenal 61.63% 1105 681 424 2014
138 sur O above, over O surreal, surrender 12.50% 96 12 84 2014
139 sy O together, with O system 0.00% 38 0 38 2014
140 syl O together, with O syllable 0.00% 7 0 7 2014
141 sym O together, with O symbol 16.07% 56 9 47 2014
142 syn O together, with O synthesis 24.68% 154 38 116 2014
143 tele O at a distance O television 50.00% 494 247 247 2014
144 trans O across, from one place to another O transatlantic, transverse 49.54% 1191 590 601 2014
145 tri O three O tricycle 60.02% 908 545 363 2014
146 twi O two O twilight 3.23% 31 1 30 2014
147 ultra O beyond, extremely O ultraviolet, ultrasonic 41.34% 762 315 447 2014
148 un N not, opposite of N unnecessary, unequal 59.38% 2868 1703 1165 2012
reverse action, deprive of, release from N undo, untie
149 under B lower in grade/dignity, lesser, insufficient N underachieve 45.13% 749 338 411 2014
below, beneath O underground, underpass
150 uni O one O unicycle 41.07% 319 131 188 2014
151 up O to make something more, higher or better O upgrade 25.53% 329 84 245 2016
152 vice O deputy O vice-president 70.59% 17 12 5 2014
153 with O against O withstand 17.86% 28 5 23 2014