"an associate in office, employment, or labor," 1530s, from French collègue (16c.), from Latin collega "partner in office," from assimilated form of com "with, together" (see com-) + leg-, stem of legare "send as a deputy, send with a commission," from PIE root *leg- (1) "to collect, gather." So, "one sent or chosen to work with another," or "one chosen at the same time as another."
Proto-Indo-European root meaning "to collect, gather," with derivatives meaning "to speak" on the notion of "to gather words, to pick out words."
It forms all or part of: alexia; analects; analogous; analogue; analogy; anthology; apologetic; apologue; apology; catalogue; coil; colleague; collect; college; collegial; Decalogue; delegate; dialect; dialogue; diligence; doxology; dyslexia; eclectic; eclogue; elect; election; epilogue; hapax legomenon; homologous; horology; ideologue; idiolect; intelligence; lectern; lectio difficilior; lection; lector; lecture; leech (n.2) "physician;" legacy; legal; legate; legend; legible; legion; legislator; legitimate; lesson; lexicon; ligneous; ligni-; logarithm; logic; logistic; logo-; logogriph; logopoeia; Logos; -logue; -logy; loyal; monologue; neglect; neologism; philology; privilege; prolegomenon; prologue; relegate; sacrilege; select; syllogism; tautology; trilogy.
It is the hypothetical source of/evidence for its existence is provided by: Greek legein "to say, tell, speak, declare; to count," originally, in Homer, "to pick out, select, collect, enumerate;" lexis "speech, diction;" logos "word, speech, thought, account;" Latin legere "to gather, choose, pluck; read," lignum "wood, firewood," literally "that which is gathered," legare "to depute, commission, charge," lex "law" (perhaps "collection of rules"); Albanian mb-ledh "to collect, harvest;" Gothic lisan "to collect, harvest," Lithuanian lesti "to pick, eat picking;" Hittite less-zi "to pick, gather."
1590s (implied in colloguing) "to flatter, curry favor," a word of unknown origin; perhaps from French colloque "conference, consultation" (16c., from Latin colloqui "speak together;" see colloquy) and influenced by dialogue or colleague. Intransitive sense "to have a private understanding with, conspire, collude" is from 1640s.
"colleague, associate," 1510s, from collateral (adj.). Meaning "something of value given as security" is from 1832, American English, from phrase collateral security "property, etc., given to secure the performance of a contract" (1720), in which collateral (adj.) has the sense of "aiding or confirming in a secondary way."
"colleague, fellow member," mid-15c., from Old French confrere "brother, companion" (13c.), from Medieval Latin confrater, from assimilated form of com "together, with" (see con-) + frater "brother" (from PIE root *bhrater- "brother"). Probably lost in later 17c. and reborrowed 19c. from Modern French confrère.
also co-optation, 1530s, "choice, selection, mutual choice, election to fill a vacancy" on a committee, board, or society, from Latin cooptationem (nominative cooptatio) "election," noun of action from past-participle stem of cooptare "to elect, to choose as a colleague or member of one's tribe," from assimilated form of com "with, together" (see com-) + optare "choose" (see option (n.)). Related: Cooptative.
1650s, "to select (someone) for a group or club by a vote of members," from Latin cooptare "to elect, to choose as a colleague or member of one's tribe," from assimilated form of com- "together" (see com-) + optare "choose" (see option (n.)). For some reason this defied the usual pattern of Latin-to-English adaptation, which should have yielded co-optate (which is attested from 1620s but now is rare or obsolete). Sense of "take over" is first recorded c. 1953. Related: Co-opted; co-opting.
mid-14c., "associate, fellow, comrade;" late 14c.,"habitual companion, friend;" from Middle Low German mate, gemate "one eating at the same table, messmate," from Proto-Germanic *ga-matjon, meaning "(one) having food (*matiz) together (*ga-)." For *matiz, see meat. It is built on the same notion as companion (which is thought to be a loan-translation from Germanic). Cognate with German Maat "mate," Dutch maat "partner, colleague, friend."
Meaning "one of a wedded pair" is attested from 1540s. Used as a form of address by sailors, laborers, etc., at least since mid-15c. Meaning "officer on a merchant vessel" is from late 15c.; his duty is to oversee the execution of the orders of the master or commander.
mid-12c., "protect or defend from harm," from Old French covrir "to cover, protect, conceal, dissemble" (12c., Modern French couvrir), from Late Latin coperire, from Latin cooperire "to cover over, overwhelm, bury," from assimilated form of com-, here perhaps an intensive prefix (see com-), + operire "to close, cover," from PIE compound *op-wer-yo-, from *op- "over" (see epi-) + root *wer- (4) "to cover."
Sense of "to hide or screen" is from c. 1300, that of "to put something over (something else)" is from early 14c. Sense of "spread (something) over the entire extent of a surface" is from late 14c. Military sense of "aim at" is from 1680s; newspaper sense first recorded 1893; use in U.S. football dates from 1907. Betting sense "place a coin of equal value on another" is by 1857. Of a horse or other large male animal, as a euphemism for "copulate with" it dates from 1530s.
Meaning "to include, embrace, comprehend" is by 1868. Meaning "to pass or travel over, move through" is from 1818. Sense of "be equal to, be of the same extent or amount, compensate for" is by 1828. Sense of "take charge of in place of an absent colleague" is attested by 1970.