In reference to single things, "so as to be unified or integrated," from c. 1300. Adjective meaning "self-assured, free of emotional difficulties" is first recorded 1966. German cognate zusammen has as second element the Old High German verbal cognate of English same (Old English also had tosamne "together").
1540s, "a going together, a coming together," from Late Latin coitionem (nominative coitio) "a coming together, a meeting; copulation," noun of action from coitus, past participle of coire "to go together, come together" (see coitus). Sexual meaning "copulation" is attested in English from 1610s (coiture in the same sense is from 1570s).
late 14c., "to join together, unite; form a union or league," from Old French conjoindre "meet, come together" (12c.), from Latin coniungere "to join together," from assimilated form of com "with, together" (see con-) + iungere "to join together" (from nasalized form of PIE root *yeug- "to join"). Related: Conjoined, conjoining. Conjoined in reference to "Siamese twins" is recorded from 1749.
"united, connected, associated," late 14c., from Old French conjoint, past participle of conjoindre "to meet, come together" (12c.), from Latin coniungere "to join together," from assimilated form of com "with, together" (see con-) + iungere "to join together" (from nasalized form of PIE root *yeug- "to join." Related: Conjointly (early 14c.).
"to weave together," 1540s, verb from Latin contexere "to weave together" (see context). Obsolete after 17c.
1670s, "act or state of sticking together," from French cohsion, from Latin cohaesionem (nominative cohaesio) "a sticking together," noun of action from past participle stem of cohaerere "to stick together," from assimilated form of com "together" (see co-) + haerere "to adhere, stick" (see hesitation).