Standard Lemma guide

co-

prefix · 21 senses · updated from the 2026-07-25 local source snapshot

Definitions and examples are grouped by meaning. Pronunciation, history, word forms, translations, descendants, synonyms, antonyms, derived terms, and related words appear whenever the source provides them.

Sound

Pronunciation

Each Play button uses your device's default local English voice, or a natural local fallback. The selected voice name appears after playback. This is synthesized speech, not a source recording.

kōʹ
Received-Pronunciation: /ˈkəʊ-/
Received-Pronunciation: /ˌkəʊ-/
Canada, General-American: /ˈkoʊ-/
Canada, General-American: /ˌkoʊ-/
South-Asia: /koː/
South-Asia: /ko/
Inland-Northern-American: /ˈkoʊ-/
Inland-Northern-American: [ˈkʌo-]
Inland-Northern-American: /ˌkoʊ-/
Inland-Northern-American: [ˌkʌo-]
Wisconsin Recorded audio is listed in the source snapshot.
Australian: /ˈkəʉ-/
Australian: /ˌkəʉ-/
New-Zealand: /ˈkɐʉ-/
New-Zealand: /ˌkɐʉ-/
unstressed: kŏ
unstressed: /kɒ-/

prefix

Meaning 1

Together: the root word is done co-incidently.

Jointly: the root verb is done in coordination between multiple actors or entities

Definition source: English Wiktionary via Wiktextract

Usage: morpheme

Examples

coadoption
coadapt
coanalysis

Meaning relationships

Synonyms: none provided

Antonyms: none provided

prefix

Meaning 2

Together: the root word is done co-incidently.

Along with: the root verb is done along with or in addition to others.

Definition source: English Wiktionary via Wiktextract

Usage: morpheme

Examples

coassemble
coadhesion
coadsorb

Meaning relationships

Synonyms: none provided

Antonyms: none provided

prefix

Meaning 3

Together: the root word is done co-incidently.

Mutually: the root is done in a way that is reciprocal and bidirectional.

Definition source: English Wiktionary via Wiktextract

Usage: morpheme

Examples

coadherence
coattraction
coannihilate

Meaning relationships

Synonyms: none provided

Antonyms: none provided

prefix

Meaning 4

Together: the root word is done co-incidently.

Simultaneously, done or able to do at the same time.

Definition source: English Wiktionary via Wiktextract

Usage: morpheme

Examples

cobirthing
cosexual
cocluster
coagglutination

Meaning relationships

Synonyms: none provided

Antonyms: none provided

prefix

Meaning 5

Together: the root word is done co-incidently.

Spatially located or positioned together, co-located.

Definition source: English Wiktionary via Wiktextract

Usage: morpheme

Examples

cocirculate
coarctate
coattend

Meaning relationships

Synonyms: none provided

Antonyms: none provided

prefix

Meaning 6

Together: the root word is done co-incidently.

In conjunction: the root needs another entity to take effect, or there is a one-way interaction between them.

Definition source: English Wiktionary via Wiktextract

Usage: morpheme

Examples

coantioxidant
codepletion
comedication

Meaning relationships

Synonyms: none provided

Antonyms: none provided

prefix

Meaning 7

Together: the root word is done co-incidently.

Moving or oriented in the same direction; co-directional.

Definition source: English Wiktionary via Wiktextract

Usage: morpheme

Examples

coflowing
cocurrent
coalign

Meaning relationships

Synonyms: none provided

Antonyms: none provided

prefix

Meaning 8

Together: the root word is done co-incidently.

Gender-mixed; having men and women together for the root activity or location.

Definition source: English Wiktionary via Wiktextract

Usage: morpheme

Examples

co-corrections
co-educate

Meaning relationships

Synonyms: none provided

Antonyms: none provided

prefix

Meaning 9

Having commonality, similarity with respect to the root.

Definition source: English Wiktionary via Wiktextract

Usage: morpheme

Examples

coaxial
cobelligerent
coaltitude

Meaning relationships

Synonyms: none provided

Antonyms: none provided

prefix

Meaning 10

Having commonality, similarity with respect to the root.

Coequal, equal in rank.

Definition source: English Wiktionary via Wiktextract

Usage: morpheme

Examples

coadministrator
coassessor
cocaptain

Meaning relationships

Synonyms: none provided

Antonyms: none provided

prefix

Meaning 11

Having commonality, similarity with respect to the root.

Indicating a family relationship that indicates a common rank made through three degrees of separation, the middle of which is by marriage.

Definition source: English Wiktionary via Wiktextract

Usage: morpheme

Examples

co-sister
co-parent-in-law
co-husband

Meaning relationships

Synonyms: none provided

Antonyms: none provided

prefix

Meaning 12

Having commonality, similarity with respect to the root.

Equally, equal with respect to the root.

Definition source: English Wiktionary via Wiktextract

Usage: morpheme

Examples

codominant
coextension

Meaning relationships

Synonyms: none provided

Antonyms: none provided

prefix

Meaning 13

Having commonality, similarity with respect to the root.

During the same time period as the root.

Definition source: English Wiktionary via Wiktextract

Usage: morpheme

Examples

coseasonal
coseismic
cotemporality

Meaning relationships

Synonyms: none provided

Antonyms: none provided

prefix

Meaning 14

Complementary in some formal manner.

The difference from some fixed quantity.

Definition source: English Wiktionary via Wiktextract

Usage: morpheme

Topics: mathematics, sciences

Examples

coaltitude
colatitude

Meaning relationships

Synonyms: none provided

Antonyms: none provided

prefix

Meaning 15

Complementary in some formal manner.

Dual, relating to the opposite category.

Definition source: English Wiktionary via Wiktextract

Usage: morpheme

Topics: mathematics, sciences

Examples

cocategory
colimit
cocone
coalgebra

Meaning relationships

Synonyms: none provided

Antonyms: none provided

prefix

Meaning 16

Having multiple targets or effects; the root affects or involves multiple subjects.

Definition source: English Wiktionary via Wiktextract

Usage: morpheme

Examples

coaccused
coaccumulation
coadsorption

Meaning relationships

Synonyms: none provided

Antonyms: none provided

prefix

Meaning 17

Secondary or auxiliary in rank or priority.

Definition source: English Wiktionary via Wiktextract

Usage: morpheme

Examples

copilot
coabuser
cofeature
coname

Meaning relationships

Synonyms: none provided

Antonyms: none provided

prefix

Meaning 18

Referring to coenzymes.

Definition source: English Wiktionary via Wiktextract

Usage: morpheme

Topics: biochemistry, biology, chemistry, microbiology, natural-sciences, physical-sciences

Examples

coglucosidase
coprotease
codehydrogenase

Meaning relationships

Synonyms: none provided

Antonyms: none provided

prefix

Meaning 19

Referring to copolymers.

Definition source: English Wiktionary via Wiktextract

Usage: morpheme

Topics: chemistry, natural-sciences, organic-chemistry, physical-sciences

Examples

codimer
copolypeptide
comonomer

Meaning relationships

Synonyms: none provided

Antonyms: none provided

prefix

Meaning 20

Deriving from multiple sources.

Definition source: English Wiktionary via Wiktextract

Usage: morpheme

Topics: chemistry, natural-sciences, physical-sciences

Examples

copolymer
cointercalation
coconformation

Meaning relationships

Synonyms: none provided

Antonyms: none provided

prefix

Meaning 21

Initialism of class of; prefixed to a full or abbreviated year number.

Definition source: English Wiktionary via Wiktextract

Usage: abbreviation, alt-of, informal, initialism, morpheme

Examples

Class of 2025 (co25) Graduation Information

Meaning relationships

Synonyms: none provided

Antonyms: none provided

History

Etymology

Etymology tree Proto-Indo-European *ḱe? Proto-Indo-European *ḱóm Proto-Italic *kom Proto-Italic *kom- Latin con- Latin co-der. English co- From Latin co-, allomorph of Latin con-.

Initialism of class of.

Across languages

Translations

43 source translations are retained for this English entry.

Asturian: co- — together, mutually, jointly
Catalan: co- — together, mutually, jointly
Czech: spolu- — together, mutually, jointly
Czech: sou- — together, mutually, jointly
Danish: sam- — together, mutually, jointly
Dutch: mede- — together, mutually, jointly
Esperanto: kun- — together, mutually, jointly
Finnish: yhteis- — together, mutually, jointly
French: co- — together, mutually, jointly
North Frisian: mä- — together, mutually, jointly
Galician: co- — together, mutually, jointly
Georgian: თანა- (tana-) — together, mutually, jointly
German: ko- — together, mutually, jointly
German: mit- — together, mutually, jointly
Hindi: सम्- (sam-) — together, mutually, jointly
Hindi: सं- (sã-) — together, mutually, jointly
Hindi: हम- (ham-) — together, mutually, jointly
Ido: kun- — together, mutually, jointly
Indonesian: ko- — together, mutually, jointly
Irish: comh- — together, mutually, jointly
Italian: co- — together, mutually, jointly
Northern Kurdish: hev- — together, mutually, jointly
Latin: co- — together, mutually, jointly
Low German: met- — together, mutually, jointly
Low German: mit- — together, mutually, jointly
Norwegian: sam- — together, mutually, jointly
Persian: همـ (ham-) — together, mutually, jointly
Polish: współ- — together, mutually, jointly
Portuguese: co- — together, mutually, jointly
Russian: со- (so-) — together, mutually, jointly
Russian: ко- (ko-) — together, mutually, jointly
Russian: взаимо- (vzaimo-) — together, mutually, jointly
Sanskrit: सम्- (sam-) — together, mutually, jointly
Sanskrit: सं- (saṃ-) — together, mutually, jointly
Serbo-Croatian: sa- — together, mutually, jointly
Serbo-Croatian: su- — together, mutually, jointly
Spanish: co- — together, mutually, jointly
Swedish: ko- — together, mutually, jointly
Swedish: med- — together, mutually, jointly
Tagalog: ka- — together, mutually, jointly
Tigrinya: ብሓባር- (bəḥabar-) — together, mutually, jointly
Unami: wit- — together, mutually, jointly
Urdu: ہمـ (ham-) — together, mutually, jointly

Word forms

Inflections and variants

No separate word forms were provided.

Word family

Derived and related words

Derived: coact, coaction, coactivation, coactive, coactivity, coactualization, coadapt, coaddict, coadministrate, coadmit, coadoption, coadventure, coaggregation, coalignment, coanalysis, coanalyze, coanchor, coappearance, coapplication, coaration, coarctate, coassist, coassistance, coassume, coattest, coattestation, coawareness, cocaptain, co-chair, cochair, cocompose, cocomposer, cocomposition, coconscious, coconspire, coconstitute, coconstrain, coconstruct, coconstructive, cocreate, cocreation, cocreative, co-credit, cocurate, cocuration, codebtor, codebug, codefine, codesign, codetermine, codevelop, codevelopment, codirect, codirection, codiscover, codiscoverer, codiverge, codivergent, codominant, codominated, codrive, coedit, coeffect, coefficacy, coefficiency, coemperor, coenact, coencapsidate, coestablishment, coestimated, coeternal, coevolution, co-evolve, coexpansion, coexperience, coextinct, cofacilitate, cofacilitation, cofinance, co-fire, cofractionate, cofractionated, co-fund, cofunded, cogeneration, cogenerative, cogrowth, coguarantor, coguardian, cohead, coheadline, coheadliner, co-host, cohost, coimmunofluorescence, coimperium, coincubate, coinfect, coinfluence, coingest, coinheritance, coinhibition, coinquirer, coinstall, coinstantiate, coinsurance, coinsure, coinsurer, coinvasion, coinvent, coinvention, coinventor, coinvest, coinvestigate, coinvestigation, coinvestment, cojoin, colanguage, colead, colessor, colicense, colimitation, comanage, comanagement, co-meddled, comembership, comodulate, comodulation, conominee, co-official, coordinance, co-own, co-ownership, co-parent, coparticipate, coparticipation, copartner, copay, cophenetic, coplot, copoiesis, copractitioner, coprecipitant, copreservation, coprimacy, coprincipality, coproduce, coproducer, copropagation, coprosperity, copublication, copublish, corear, coredeem, coredemption, coregulator, coreign, corelease, coreport, coreporter, corequirement, coresident, co-responsibility, co-responsible, corotation, coscreenplay, coscreenwriter, coscript, cosentient, cosign, cosignatory, co-sounding, cosovereignty, cospecialize, cosponsor, cosponsorship, costatement, cosupervise, cosupervision, cosurety, cotenancy, cotenure, cotillage, cotranslate, cotranslation, cotutelage, counite, covolatility, coactivated, coadded, coaddition, coadhesion, coadhesive, coadminister, coadministered, coadsorb, coaggregate, co-agonist, coagroinfiltrated, coamplification, coapply, coassemble, coauthor, cobelligerent, cobless, coboard, cobound, co-branding, cobuild, cocite, co-conspirator, cocultivate, cocurricular, codeleted, codenaturated, codenaturation, codenature, codepleted, codeposit, codissolve, codistributed, codominate, codoped, codoping, coelevated, coemergence, coencapsulate, coendemic, co-endure, coevolve, coexhibit, coexport, coexpress, coextend, coextrude, co-feed, cofeed, cofiltered, cofluctuate, coformulated, cofostered, cofound, cogovern, coharbour, cohemolytic, cohybridize, coimmobilisation, coimmunofluorescent, coimmunopurify, coimplantation, coimpregnated, coincorporation, coinduce, coinfectant, coinfective, coinfiltrate, coinfiltration, coinfuse, coinherit, coinhibit, coinhibitor, coinhibitory, coinoculate, coinstantiation, cointegrant, cointernalize, cointernalized, cointroduce, coinvade, coisolate, coisolation, colabel, colegislate, colimit, colinearize, comanufacture, comitogenic, comodified, cooccupy, coordain, coossified, coossify, copanellist, coparalogous, copassenger, copathogenesis, copathology, coplayer, copolymerized, coprescribe, copresent, coregistered, coregistrated, coregulate, corepress, coresistant, corotate, cosecreted, cosedimentation, coseeded, cosegregate, cosegregated, coshift, cosonicate, cospeciate, co-speech, costimulant, costratification, cosynthesized, coteach, coterminate, coterminated, cotest, cotext, cotransduce, cotransduced, cotransfect, cotransferred, cotranslocate, cotranslocation, cotransmission, cotransmit, cotravel, covary, coventilated, coverbal, cowrite, coactor, coaddressee, coadministration, coadministrator, coally, coambassador, coarbitrator, coarchitect, coassessor, coassignee, coauditor, co-aunt, coauthorship, cobishop, cocaptaincy, co-CEO, cochairman, cochairperson, cochairwoman, cochampion, cochief, co-commander, cocommentator, coconstruction, coconsul, cocounsel, cocreator, cocurator, codesigner, codeveloper, codictatorship, codirector, codrawer, coeditor, coestate, coexecutant, coexecutor, coexecutrix, cofacilitator, co-father, cofavorite, cofeoffee, cofilmmaker, cofounder, cogovernor, coheir, coheiress, coherald, coheritor, coholder, cohostess, coinheritor, coinmate, coinventorship, coinvestigator, coinvestor, colaborer, coleader, colecturer, colegatee, colessee, co-linguist, comanager, comediator, comortgagee, cooperator, coorganizer, co-owner, copacker, coparcenary, copartaker, coparticipant, copartisan, copartnership, copastor, copatentee, copatriot, copatron, copayer, copetitioner, copresenter, copresident, coprince, coprincipal, coprisoner, copromoter, coproprietor, coprotagonist, copublisher, copurchaser, corecipient, coredeemer, coredemptress, coredemptrix, coregent, coregnant, co-religionary, co-religionist, coresearcher, coruler, coscenarist, co-scripter, cosettler, cosigner, cosleeper, cosovereign, co-spy, costar, cosupervisor, cosustainer, coteacher, cotitular, cotortfeasor, cotraitor, cotranslator, cotrustee, cotutor, co-uncle, covaledictorian, covisitor, cowinner, coworker, cowriter, coagglutination, coarticulate, cobinding, cobirthing, cobreeding, cochromatography, cocirculation, co-citation, cocluster, coclustering, cocolonization, cocondensation, coconsumption, cocontraction, coconversion, cocrystallization, cocrystallize, cocultivation, codeletion, codelivery, codeposition, codetect, codetection, codigestion, codispersal, codisplay, codistillation, codistribution, codiversification, codiversify, codopant, coedition, coelectroporation, coelution, coenrich, coenrichment, coestimation, coevaluate, coexistent, coexpose, coexposure, coexpression, coextensive, coextinction, coextraction, coextrusion, cofermentation, coflowering, cofluctuation, cogenerate, cogenerator, cogenesis, coimmunolabel, coimmunolocalization, coimmunoprecipitation, coimmunoreactivity, coimmunostaining, coincidental, coinduction, coinfected, coinfection, coinjected, coinoculation, cointroduction, coinversion, colocalize, co-locate, comigration, comilling, comobilization, comorbid, comorbidity, conatal, co-occur, cooxidation, cophylogenetic, cophylogeny, coproduct, copurify, corecognition, corecruit, corecruitment, coregistration, coregulated, coregulation, coresistance, cosecretion, coseismal, coselection, cosensitization, cosexual, cosimulation, cosuppression, cosynthesis, cotargeting, cotemporal, coterminal, cotherapy, cothymia, cotranscribe, cotranscription, cotransduction, cotransfection, cotransformation, cotranslational, cotransmitter, cotransplant, cotransport, cotreat, cotreatment, cotunneling, covisualization, coadventurer, coagency, coaltitude, coaxial, co-bed, co-believer, cocelebrant, cocircular, cocitizen, cocultural, cocyclomatic, codefendant, codirectional, coequal, coessential, coethnic, coeval, cofamilial, cogenetic, coindex, coindicant, coinstantaneous, coinstantiated, coislander, coisotropic, cojuror, colingual, comagmatic, comeasurable, comember, comeronym, comeronymous, comovement, co-opinionist, coorbital, coöriginal, copack, coplaintiff, coplanar, copunctal, copunctual, coradicate, corefer, coreference, coreferent, coreferential, corotational, cosentential, cosignificative, cosingular, cosleep, cosolute, costraight, costructure, covillager, noncoreferential, coadjoint, coalgebra, coanalytic, coarea, coassociative, coassociativity, cocategory, cocenter, cocharacter, cocircuit, coclique, coclosed, cocoloring, cocone, coconform, codimension, codual, coend, coequalizer, cofinite, cofree, cofunction, cograph, cogroup, cohomotopy, cohyponormal, coimage, cokernel, colatitude, coline, comass, comeagre, comodernism, comodule, comonad, comonoid, conatural, conorm, conull, coorbit, coplane, copoint, copower, copresheaf, coquasitriangular, corecursion, coreflective, corelation, coresolution, coring, cosemisimple, cosheaf, cosimplex, cospan, cotilting, counimodular, co-adaptation, coadherence, coadjacent, coadjument, coadjust, coadjustment, coadjutant, coadjuting, coadjuvancy, coadoration, coalternate, coannihilate, coannihilation, coassociation, coattraction, cocatalyst, codeformational, co-dependent, codivergence, coequate, coequilibration, coevolutive, coexchangeable, coexistence, cofinal, cofinality, cofolding, co-fusion, coimmunoprecipitate, coinitial, coinitiality, coinitiator, co-IVF, comimetic, coorientation, coprevalence, coreachable, corepression, corespective, counion, co-vilification, coabuse, coaccumulation, coaccused, coadsorption, coamplify, cobombardment, cocapture, cocatalyzed, cochannel, cocladogenesis, coculture, codeliver, codigest, coendocytosis, coimmunization, coimmunize, coimmunostain, coincubation, coingestion, coinjection, colexification, colexify, coloaded, comajor, cooverexpression, coprescription, coprocessing, cosegmentation, costain, costaining, cotransplantation, covitrification, coappear, coattend, cocirculate, cofilament, cohouse, cohoused, coinhabit, coinhabitant, cointer, colayered, coliving, co-location, cooccupancy, copathogen, copolar, coreside, coresidence, cosediment, co-sleeping, cospatial, coworking, coadapted, coadsorbent, coanalgesic, coantioxidant, cobenefit, cocarcinogen, cocarcinogenesis, co-decision, codepletion, codrug, coenzyme, coextract, colegislator, colethal, comedication, cometabolism, conutrient, cooxidant, co-pattern, corequisite, cosolvent, co-stimulation, costimulator, co-affine, co-brother, co-brother-in-law, co-father-in-law, co-grandfather, co-grandmother, co-grandparent, co-husband, co-in-law, co-mother-in-law, co-parent-in-law, co-sibling-in-law, co-sister, co-sister-in-law, cotwin, co-wife, coabuser, coagent, codriver, cofeature, coinstaller, coname, copilot, coprocess, cosysop, cowalker, coalign, coarctation, cocurrent, codistribute, coemerge, coexpand, coflowing, colaminar, comigrate, comove, copropagating, codehydrogenase, coenzymic, cofactor, coferment, coglucosidase, colipase, coprotease, cosubstrate, codimer, coglycolide, comonomer, copolyester, copolyimide, copolymerase, copolymerizable, copolymerize, copolypeptide, coconformation, cocrystal, cointercalation, copolymer, copurification, coreactant, cotrimerization, codominance, coeternity, coextension, co-corrections, co-educate, coeducation, Co-Freemasonry, cogender, coseasonal, coseismic, cotemporality

Related: school class, CO-

Semantic map

Other relationships

Sources

Where this information comes from

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