Origin and history of tidbit

"small piece," c. 1200; related Old English bite "act of biting," and bita "piece bitten off," which probably are the source of the modern words meaning "boring-piece of a drill" (the "biting" part, 1590s), "mouthpiece of a horse's bridle" (mid-14c.), and "a piece (of food) bitten off, morsel" (c. 1000). All from Proto-Germanic *biton (source also of Old Saxon biti, Old Norse bit, Old Frisian bite, Middle Dutch bete, Old High German bizzo "biting," German Bissen "a bite, morsel"), from PIE root *bheid- "to split."

The meaning "small piece, fragment" of anything is from c. 1600. The sense of "short space of time" is 1650s. Theatrical bit part is from 1909. The colloquial sense of "small coin" in two bits, etc. is originally from the U.S. South and the West Indies, in reference to silver wedges cut or stamped from Spanish dollars (later Mexican reals); transferred to "eighth of a dollar."

1540s, a word used for a small or poor horse, also later of any small animal or object, as in bird names titmouse, tom-tit, titlark (1660s), titling "pipit" (1819); tit-babbler (1893), etc. Century Dictionary has titty-todger "wren." Similar words in related senses are found in Scandinavian (Icelandic tittr, Norwegian tita "a little bird;" Old Norse titlingr "a sparrow"), but the connection and origin are obscure; perhaps, as OED (1989) suggests, the word is merely suggestive of something small. Or perhaps the typical chip-chipping sound of a small bird.

It is attested by 1706 as short for titmouse. It was used figuratively of persons by 1734, but earlier it was "girl or young woman" (1590s, common 17c.-18c.), often in deprecatory sense of "hussy, minx." Also compare titter (n.) "girl, young woman" (1812, slang); titty "sister, young girl" (1728), also "a cat" (1821). For these senses compare pussy (n.1), kitty (n.1).

also titbit, "delicate bit (of food), sweet morsel," 1630s; see tidbit.