Origin and history of tail-hook

"bent or angled piece of metal or other substance used to catch or hold something," Old English hoc "hook, angle," perhaps related to Old English haca "bolt," from Proto-Germanic *hokaz/*hakan (source also of Old Frisian hok, Middle Dutch hoek "a hook;" Dutch haak "a hook, angle, corner, cape," German Haken "hook"), from PIE root *keg- "hook, tooth." For spelling, see hood (n.1).

Also the name of a fireman's tool for tearing into buildings, hence hook-and-ladder (1821). Meaning "holder for a telephone receiver" is from 1885 and continued in use after the mechanism evolved. Boxing sense of "short, swinging blow with the elbow bent" is from 1898. Figurative sense "that which catches, a snare, trap" is from early 15c. Meaning "projecting point of land" is from 1670s; in U.S. use probably reinforced by the Dutch word.

This name is given in New York to several angular points in the North and East rivers; as Corlear's Hook, Sandy Hook, Powles's Hook. [Bartlett, "Dictionary of Americanisms," 1848]

Off the hooks meant "disordered" (16c.), "unhinged" (1610s) and "dead" (1840). By hook or by crook (late 14c.) probably alludes to tools of professional thieves. Hook, line, and sinker "completely" is 1838, a metaphor from angling. Hook-nose (n.) is from 1680s; hook-nosed (adj.) from 1510s. Hook-and-eye as a method of garment fastening is from 1620s.

Hook and eye, a metallic fastening for garments, consisting of a hook, commonly of flattened wire bent to the required shape, and an eye, usually of the same material, into which the hook fits. Under the name of crochet and loop, this form of fastening was in use as early as the fourteenth century. [Century Dictionary]

[hindmost part of an animal] Old English tægl, tægel "posterior extremity," from Proto-Germanic *tagla- (source also of Old High German zagal, German Zagel "tail," dialectal German Zagel "penis," Old Norse tagl "horse's tail," Gothic tagl "hair"), according to Watkins from PIE *doklos, from suffixed form of root *dek- (2) "something long and thin" (referring to such things as fringe, lock of hair, horsetail; source also of Old Irish dual "lock of hair," Sanskrit dasah "fringe, wick").

 According to OED (2nd ed., 1989), the primary sense, at least in Germanic, seems to have been "hairy tail," or just "tuft of hair," but already in Old English the word was applied to the hairless "tails" of worms, bees, etc. But Buck writes that the common notion is of "long, slender shape."

 Extended to many things resembling a tail in shape or position; by late 14c. as "hinder, bottom, or concluding part" in space or time of a text, a storm, etc. As an adjective from 1670s.

 The meaning "reverse side of a coin" (opposite the side with the head) is from 1680s. Of descending strokes of letters, from 1590s. Tails "coat with tails" is from 1857, short for tail-coat.

To turn tail "wheel about, take flight" (1580s) seems to have been originally a term in falconry. The image of the tail wagging the dog is attested by 1866, American English, perhaps inspired by a much-reprinted 1863 newspaper joke:

Why does a dog wag his tail?

Because the dog is stronger than the tail; otherwise the tail would wag the dog.

[Woodcock, Illinois, Sentinel, Sept. 2, 1863]

Another Old English word for "tail" was steort (see stark). The slang sense of "pudenda" is from mid-14c.; that of "woman as sex object" is from 1933, earlier "act of copulation" with a prostitute (1846).