O.Ir. dual "lock of hair," Skt. dasah "fringe, wick"). The primary sense, at least in Gmc., seems to have been "hairy tail," or just "tuft of hair," but already in O.E. the word was applied to the hairless "tails" of worms, bees, etc. Another O.E. word for "tail" was steort (see stark
). Meaning "reverse side of a coin" is from 1680s; that of "backside of a person, buttocks" is recorded from c.1300; slang sense of "pudenda" is from mid-14c.; that of "woman as sex object" is from 1933, earlier "prostitute" (1846). The tail-race (1776) is the part of a mill race below the wheel. To turn tail "take flight" (1580s) originally was a term in falconry. The image of the tail wagging the dog is attested from 1907.
"limitation of ownership," a legal term, 1321 in Anglo-Fr.; 1284 in Anglo-L., in most cases an aphetic form of entail
"follow secretly," U.S. colloquial, 1907, is from earlier sense of "follow or drive cattle," from tail
(n.1). Tail off "diminish" is attested from 1854.