1520s, in grammatical sense; 1560s in literal sense, from Latin coniugatus, past participle of coniugare "to yoke together" (see conjugal). Earlier as an adjective (late 15c.). Related: Conjugated; conjugating.
conjugate con·ju·gate (kŏn'jə-gāt')
v. con·ju·gat·ed, con·ju·gat·ing, con·ju·gates
To undergo conjugation. adj. (-gĭt, -gāt')
Joined together, especially in pairs.
Pertaining to an acid and a base that are related by the difference of a proton.