Origin and history of coit

"copulation, sexual intercourse," 1848, scientific use of Latin coitus "a meeting together; sexual union," past participle of coire "to come together, meet," from assimilated form of com "together" (see co-) + ire (past participle itus) "to come, to go," (from PIE root *ei- "to go").

In Middle English nativized as coite (early 15c.). Coitus was used in English in general senses of "meeting, uniting," and also in reference to magnetic force, planetary conjunction, etc., before the sexual sense came to predominate.

Coitus interruptus, "sexual intercourse in which the penis is voluntarily withdrawn from the vagina before ejaculation, for the purpose of avoiding conception," is from 1886 (from 1885 in German publications). Coitus reservatus in reference to prolonged copulation by deliberate control is from 1890 in English (1880 in German).

late 14c., coyte (Anglo-French), "a flat stone thrown in a game," later also a ring of iron used the same way (15c.); a word of uncertain origin; probably from Old French coite "flat stone," which is perhaps literally "cushion," and a variant of coilte (see quilt (n.)).

Quoits were among the games prohibited by Edward III and Richard II to encourage archery. In reference to the tossing game played with iron rings, from mid-15c.

Formerly in the country, the rustics not having the round perforated quoits to play with, used horse-shoes, and in many places the quoit itself, to this day, is called a shoe. [Joseph Strutt, "Sports and Pastimes of the People of England," 1801]