"turtledove," Old English turtle, dissimilation of Latin turtur "turtledove," a reduplicated form imitative of the bird's coo. Graceful, harmonious and affectionate to its mate, hence a term of endearment in Middle English. Turtle-dove is attested from c. 1300.

c. 1200, "action of rotating," from Anglo-French tourn (Old French torn, tour), from Latin tornus "turning lathe;" also partly from turn (v.). Meaning "an act of turning, a single revolution or part of a revolution" is attested from late 15c. Sense of "place of bending" (in a road, river, etc.) is recorded from early 15c. Meaning "beginning of a period of time" is attested from 1853 (as in turn-of-the-century, from 1921 as an adjectival phrase).

Sense of "act of good will" is recorded from c. 1300. Meaning "spell of work" is from late 14c.; that of "an individual's time for action, when these go around in succession" is recorded from late 14c. The automatic automobile turn-signal is from 1915. Turn-sick "dizzy," is attested from early 15c. Phrase done to a turn (1780) suggests meat roasted on a spit. The turn of the screw (1796) is the additional twist to tighten its hold, sometimes with reference to torture by thumbscrews.

late Old English turnian "to rotate, revolve," in part also from Old French torner "to turn away or around; draw aside, cause to turn; change, transform; turn on a lathe" (Modern French tourner), both from Latin tornare "to polish, round off, fashion, turn on a lathe," from tornus "lathe," from Greek tornos "lathe, tool for drawing circles," from PIE root *tere- (1) "to rub, turn." Transitive sense in English is from c. 1300. Related: Turned; turning.

Use in expression to turn (something) into (something else) probably retains the classical sense of "to shape on a lathe." To turn up "arrive, make an appearance" is recorded from 1755. Turn about "by turns, alternately" is recorded from 1640s. To turn (something) loose "set free" is recorded from 1590s. Turn down (v.) "reject" first recorded 1891, American English. Turn in "go to bed" is attested from 1690s, originally nautical. To turn the stomach "nauseate" is recorded from 1620s. To turn up one's nose as an expression of contempt is attested from 1779.

Turning point is attested by 1640s in a figurative sense "point at which a decisive change takes place;" literal sense "point on which a thing turns; point at which motion in one direction ceases and that in another or contrary direction begins" is from 1660s.

"tortoise," c. 1600, originally "marine tortoise," from French tortue, tortre (13c.) "turtle, tortoise" (often associated with diabolical beasts), of unknown origin. The English word perhaps is a sailors' mauling of the French one, influenced by the similar sounding turtle (n.2). Later extended to land tortoises; sea-turtle is attested from 1610s.

"audience, assemblage of persons who have come to see a show, spectacle, etc.," 1816, from the verbal phrase; see turn (v.) + out (adv.).

that which arouses or excites, 1968, originally of psychedelic drugs, from verbal phrase turn on "activate (a mechanism)" (1833), specifically from figurative sense turn (someone) on "excite, stimulate, arouse," recorded from 1903; from turn (v.) + on (adv.).

1934, from U + turn (n.). So called in reference to the shape of the path described.

also turnaround, 1936, from verbal phrase turn around "reverse," 1880, American English, from turn (v.) + around (adv.).

tortoise-like land-dwelling turtle of North America, 1825, American English for what is called by English writers a box-tortoise (1834), from box (n.1), so called for its resemblance to a tight, closed box when the head, tail, and legs are drawn in.

"something that dampens one's spirits" recorded by 1971 (said to have been in use since 1968), from verbal phrase turn off "stop the flow of" (1850), from turn (v.) + off (adv.). Turn-off (n.) as "place where one road diverges from another" is from 1881.