"uniting, serving to couple," late 14c., from Late Latin copulativus, from copulat-, past-participle stem of Latin copulare "to join together, link, unite," from copula "a band, tie, link" (see copulate). Related: Copulatively.
"to dwell together," specifically "to dwell together as husband and wife," 1530s, a back-formation from cohabitation (q.v.) or else from Late Latin cohabitare. A euphemism to describe a couple living together without benefit of marriage and usually implying sexual intercourse. Related: Cohabited; cohabiting.
c. 1500, transitive, "to equal, rival," 1590s as "to match as mates, couple, join in marriage," from mate (n.1). Also, of animals, "to pair for the purpose of breeding" (c. 1600). Intransitive sense of "be joined in companionship" is from 1580s. Related: Mated; mating.
mid-13c., paire, "a set of two, two of a kind coupled in use," from Old French paire "pair, couple," and directly from Medieval Latin paria "equals," neuter plural of Latin par (genitive paris) "a pair, counterpart, equal," noun use of par (adj.) "equal, equal-sized, well-matched" (see par (n.)).
Originally of things. Of persons from late 14c., "a couple, a sexual pair." Used from late 14c. with a plural noun to denote a single tool or device composed essentially of two pieces or parts (shears, tongs, spectacles, etc.). Meaning "a woman's breasts" is attested from 1922. Pair bond (v.) is first attested 1940, in reference to birds mating.
1570s, "behavior of a courtier," from court (n.) + -ship. Meaning "the wooing of a woman, attention paid by a man to a woman with intention of winning her affection and ultimately her consent to marriage" is from 1590s. By 1830s it was used of a period during which a couple mutually develops a romantic relationship with a view to marriage.