1580s, of persons, "wearing a ruff;" by 1610s in animal and bird names, "having a ruff" of feathers, etc., from ruff (n.1). The American ruffed grouse is so called by 1782.
1560s, "to move and act unconsciously;" 1580s, "to be listless and apathetic," the sound of the word perhaps somehow suggestive of low feelings (compare mop (v.) "make a wry mouth" (1560s); Low German mopen "to sulk," Dutch moppen "to grumble, to grouse," Danish maabe, dialectal Swedish mopa "to mope"). Related: Moped; moping; mopey; mopish.
bird of the grouse family, 1590s, from Gaelic tarmachan, a word of unknown origin. The unetymological pt- spelling (1680s) began in French and seems to be a mistaken Greek construction (perhaps based on pteron "wing").
small migratory game bird of the Old World, 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, Portuguese calha, Old Spanish coalla), or directly from a Germanic source (compare Dutch kwakkel, Old High German quahtala "quail," German Wachtel, Old English wihtel), imitative of the bird's cry. Or the English word might have come up indigenously from Proto-Germanic.
Slang meaning "young attractive woman" is attested by 1859. Applied to similar birds in the New World.
Among such, the species of bob-white, as Ortyx virginiana, the common partridge or quail of sportsmen, are the nearest to the Old World species of Coturnix. In the United States, wherever the ruffed grouse, Bonasa umbella, is called pheasant, the bob-white is called partridge: where that grouse is called partridge, the bob-white is known as quail. [Century Dictionary, 1897]
c. 1200, "to clutch, seize firmly," from Old English gripan "grasp at, lay hold, attack, take, seek to get hold of," from Proto-Germanic *gripan (source also of Old Saxon gripan, Old Norse gripa, Dutch grijpen, Gothic greipan, Old High German grifan, German greifen "to seize"), of uncertain origin, perhaps from PIE root *ghreib- "to grip" (source also of Lithuanian griebiu, griebti "to seize"). Figurative sense of "complain, grouse" is first attested 1932, probably from earlier meaning "produce a gripping pain in the bowels" (c. 1600; compare belly-ache). Related: Griped; griping.
"tract of open, untilled, more or less elevated ground, often overrun with heath," c. 1200, from Old English mor "morass, swamp," from Proto-Germanic *mora- (source also of Old Saxon, Middle Dutch, Dutch meer "swamp," Old High German muor "swamp," also "sea," German Moor "moor," Old Norse mörr "moorland," marr "sea"), perhaps related to mere (n.1), or from root *mer- "to die," hence "dead land."
The basic sense in place names is 'marsh', a kind of low-lying wetland possibly regarded as less fertile than mersc 'marsh.' The development of the senses 'dry heathland, barren upland' is not fully accounted for but may be due to the idea of infertility. [Cambridge Dictionary of English Place-Names]
Hence moor-fowl "grouse" (c. 1500); moor-hen (mid-14c.); moor-cock (c. 1200 as a surname).