"to mend (fabric) by interweaving yarn or thread to fill a rent or hole," c. 1600, of unknown origin. Perhaps from French darner "mend," from darne "a piece, a slice," from Breton darn "piece, fragment, part." Alternative etymology is from obsolete dern "secret, hidden." Related: Darned; darning.

late 14c., twiteren, in reference to birds, of imitative origin (compare Old High German zwizziron, German zwitschern, Danish kvidre, Old Swedish kvitra). The noun meaning "condition of tremulous excitement" is attested from 1670s. The microblogging service with the 140-character limit was introduced in 2006. The following is considered an unrelated word of obscure origin:

TWITTER. 1. "That part of a thread that is spun too small." Yarn is said to be twined to twitters, when twined too small, S. Hence, to twitter yarn, to spin it unequally, A. Bor. Ray.

2. It is transferred to any person or thing that is slender or feeble. It is said of a lank delicate girl: "She is a mere twitter," S. [Jamieson, "Etymological Dictionary of the Scottish Language," Edinburgh, 1808]

"to indicate by means of a clue," 1934; "to inform someone of the important facts," usually with in, 1948, from clue (n.). Related: Clued; cluing. Earlier in now-obsolete sense of "follow or track by clues" (1660s). In nautical use, "to haul up (a sail) by means of the clue-lines," from clue (n.) in the "wound ball of yarn" sense.

"accumulation; ball," 1620s, from Latin glomerationem (nominative glomeratio), noun of action from past-participle stem of glomerare "to wind or form into a ball, roll together, collect," from glomus "ball of yarn, ball-shaped mass," from Proto-Italic *glemos-, from PIE *glem- or *glom-, perhaps originally "ball," but the reconstruction is uncertain (see glebe).

1774, "action of collecting in a mass," from Latin agglomerationem (nominative agglomeratio), noun of action from past-participle stem of agglomerare "to wind or add onto a ball," from ad "to" (see ad-) + glomerare "wind up in a ball," from glomus (genitive glomeris) "ball, ball of yarn, ball-shaped mass," which is of uncertain origin (see glebe). In reference to a mass so formed, it is recorded from 1833.

"to move with a winding motion," a word used in poetry by Yeats from c. 1920, probably from a variant of dialectal pirn (n.) "small cylinder on which thread or yarn is wound (mid-15c.), which seems to have survived in dialects in Celtic parts of Britain. It is perhaps from prin "a twig, shoot of a tree" (c.1400), itself a variant of prene "a nail, spike," from Old English preon.