- tack (1)
- "clasp, hook, fastener," 1296, from O.N.Fr. taque "nail, pin, peg," probably from a Gmc. source (cf. M.Du. tacke "twig, spike," Low Ger. takk "tine, pointed thing," Ger. Zacken "sharp point, tooth, prong"); perhaps related to tail. Meaning "small, sharp nail with a flat head" is attested from 1463. Verb sense of "to attach as a supplement" (with suggestion of hasty or arbitrary proceeding) is attested from 1683. The meaning "rope to hold the corner of a sail in place" is first recorded 1481; hence the verb meaning "sail into the wind," first recorded 1557, which lead to the fig. sense of "course or line of conduct or action" (1675).
- tack (2)
- "horse's harness, etc.," 1924, shortening of tackle in sense of "equipment." Tack in a non-equestrian sense as a shortening of tackle is recorded in dialect from 1777.
- tack (3)
- "food," 1833, perhaps a shortening and special use of tackle in the sense of "gear." Hard-tack was originally "ship's biscuit," soft-tack being bread.