migratory game bird, late 14c. (early 14c. as a surname (Quayle), from Old French quaille (Modern French caille), perhaps via Medieval Latin quaccula (source also of Provençal calha, Italian quaglia, Old Spanish coalla), or directly from a Germanic source (cf. Dutch kwakkel, Old High German quahtala "quail," German Wachtel, Old English wihtel), imitative of the bird's cry. Or the English word might be directly from Proto-Germanic. Slang meaning "young attractive woman" first recorded 1859.
c.1400, "have a morbid craving;" early 15c., "grow feeble or sick;" mid-15c., "to fade, fail, give way," of unknown origin, perhaps from Middle Dutch quelen "to suffer, be ill," from Proto-Germanic *kwel- "to die" (see quell). Or from obsolete quail "to curdle" (late 14c.), from Old French coailler, from Latin coagulare (see coagulate). Sense of "lose heart, shrink, cower" is attested from 1550s. According to OED, common 1520-1650, then rare until 19c., when apparently it was revived by Scott. Related: Quailed; quailing.
The Israelites were twice relieved in their privation by a miraculous supply of quails, (1) in the wilderness of Sin (Ex. 16:13), and (2) again at Kibroth-hattaavah (q.v.), Num. 11:31. God "rained flesh upon them as dust, and feathered fowls like as the sand of the sea" (Ps. 78:27). The words in Num. 11:31, according to the Authorized Version, appear to denote that the quails lay one above another to the thickness of two cubits above the ground. The Revised Version, however, reads, "about two cubits above the face of the earth", i.e., the quails flew at this height, and were easily killed or caught by the hand. Being thus secured in vast numbers by the people, they "spread them all abroad" (11:32) in order to salt and dry them. These birds (the Coturnix vulgaris of naturalists) are found in countless numbers on the shores of the Mediterranean, and their annual migration is an event causing great excitement.