Online Etymology Dictionary

vireo (n.): small American bird, 1834, a modern use of Latin vireo, a word Pliny applied to some kind of bird, believed to be the European greenfinch, from virere "be green" (see verdure).
auk (n.): 1670s, from a Scandinavian source such as Old Norse alka, probably originally imitative of a water-bird cry (compare Latin olor "swan," Greek elea "marsh bird").
bustard (n.): large crane-like bird, mid-15c. (late 14c. as a surname), from Old French bistarde, said to be from Latin avis tarda, but the sense of this ("slow bird") is the opposite of the bird's behavior.
nestling (n.): late 14c., "bird too young to leave the nest," from nest (n.) + diminutive suffix -ling.
dicky (n.): "detached shirt front," 1811; "a small bird," 1851; diminutive of dick, but the applications are obscure in both cases.
loon (n.1): large diving bird (especially the Great Northern Diver), 1630s, from a Scandinavian source (compare Norwegian lom, from Old Norse lomr).
archaeopteryx (n.): oldest known fossil bird, 1859, Modern Latin, from archaeo- "ancient, primitive" + Greek pteryx "wing" (see pterodactyl).
auspex (n.): 1590s, "one who observes flights of birds for the purpose of taking omens," from Latin auspex "interpreter of omens given by birds," from PIE *awi-spek- "observer of birds," from *awi- "bird" (see aviary) + *spek- "to see" (see scope (n.1)). Compare Greek oionos "bird of prey," also "bird of omen, omen," and ornis "bird," which also could mean "omen."
grosbeak (n.): general name for a bird with a large bill, 1670s, partial translation of French grosbec; see gross (adj.) + beak.
aviculture (n.): 1876, from French aviculture, from Latin avis "bird" (see aviary) + Latin cultura "cultivation" (see culture).
kingfisher (n.): type of colorful European diving bird, mid-15c., originally king's fisher, for obscure reasons; see king + fisher.
sora (n.): small, short-billed North American bird species, the Carolina rail, 1705, probably from a native name.
torii (n.): singular and plural, "gateway to a Shinto temple," Japanese, according to OED from tori "bird" + i "to sit, to perch."
redbreast (n.): early 15c., of the English robin, from red (adj.1) + breast (n.). Later of the American bird.
redstart (n.): type of bird, 1560s, from red (adj.1) + start "tail," from Old English steort. Similar formation in German Rotsterz.
wryneck (n.): 1580s, from wry + neck (n.). The bird so called from the singular manner in which is can twist the neck.
rara avis (n.): c. 1600, "peculiar person," from Latin rara avis, literally "strange bird," from rara, fem. of rarus "rare" (see rare (adj.1)) + avis "bird" (see aviary). Latin plural is raræ aves. Horace's peacock (a Roman delicacy), Juvenal's black swan ("Rara avis in terris, nigroque simillima cygno").
osprey (n.): fishing hawk, mid-15c., from Anglo-French ospriet, from Medieval Latin avis prede "bird of prey," from Latin avis praedæ, a generic term apparently confused with this specific bird in Old French on its similarity to ossifrage.
wheatear (n.): type of bird, 1590s, back-formation from white-ears, literally "white-arse" (see white + arse). So called for its color markings; compare French name for the bird, cul-blanc, literally "white rump."
simurgh (n.): monstrous bird, rational and ancient, in Persian mythology, 1786, from Persian simurgh, from Pahlavi sin "eagle" + murgh "bird." Compare Avestan saeno merego "eagle," Sanskrit syenah "eagle," Armenian cin "kite." Probably identical with the roc (q.v.).
icterus (n.): "jaundice," 1706, medical Latin, from Greek ikteros "jaundice," also the name of a yellowish bird the sight of which was supposed, by sympathetic magic, to cure jaundice (but the bird died). As a zoological genus (American orioles), from 1713.
swift (n.): type of bird (several species of the family Cypselidæ, resembling swallows), 1660s, from swift (adj.) in reference to its swift flight. Regarded as a bird of ill-omen, if not downright demonic, probably for its shrill cry. The name earlier had been given to several small fast lizards (1520s).
ptarmigan (n.): bird of the grouse family, 1590s, from Gaelic tarmachan, of unknown origin. The pt- spelling (1680s) is a mistaken Greek construction (perhaps based on pteron "wing").
rail (n.2): "small wading bird," mid-15c., from Old French raale (13c.), related to râler "to rattle," of unknown origin, perhaps imitative of its cry.
yip (v.): 1891, possibly from dialectal yip "to cheep like a bird" (early 19c.), from Middle English yippen (mid-15c.), of imitative origin. As a noun from 1896.
nib (n.): 1580s, "beak or bill of a bird," Scottish variant of Old English neb (see neb). Meaning "point" (of a pen or quill) first recorded 1610s.
grebe (n.): diving bird, 1766, from French grèbe (16c.), of unknown origin, possibly from Breton krib "a comb," since some species are crested.
perch (v.): "to roost," late 14c., from Old French perchier "to sit on a perch" (of a bird), from perche (n.) (see perch (n.1)). Related: Perched; perching.
prion (n.): petrel-like bird, 1848, from Greek prion "a saw," related to priein, prizein "to saw, to be cut in pieces." So called for its bill.
chant (n.): 1670s, from chant (v.), or else from French chant (12c.), from Latin cantus "song, a singing; bird-song," from past participle stem of canere.
gnatho-: before vowels gnath-, word-forming element meaning "jaw, mouth part, beak (of a bird)," from Greek gnathos "jaw" (see gnathic).
dawdle (v.): 1650s, perhaps a variant of daddle "to walk unsteadily." Perhaps influenced by daw, because the bird was regarded as sluggish and silly. Not in general use until c. 1775. Related: Dawdled; dawdling.
Vega (n.): 1638, bright northern star, the alpha of Lyra, from Arabic (Al Nasr) al Waqi translated variously as "the eagle of the desert" or "the falling vulture" (or bird).
emu (n.): large Australian three-toed bird, 1610s, probably from Portuguese ema "crane, ostrich" (which is of unknown origin), perhaps based on a folk-etymology of a native name.
wren (n.): small, migratory singing bird, Old English wrenna, metathesis variation of earlier werna, a Germanic word of uncertain origin. Compare Icelandic rindill, Old High German wrendo, wrendilo "wren."
grouse (n.): type of game bird, 1530s, grows (plural, used collectively), of unknown origin, possibly from Latin or Welsh. Originally the moorhen of the British Isles; later the name was extended to similar birds in other places.
roc (n.): large, ferocious bird of fable, 1570s, from Arabic rukhkh, from Persian rukh. Mentioned in Marco Polo's account of Madagascar, modern use is mostly from "Arabian Nights." Hence roc's egg "something marvelous or prodigious."
toucan: bright-colored bird of South America, 1560s, from French toucan (1550s) and Spanish tucan; from Tupi (Brazil) tuka, tukana, said to be probably imitative of its call.
dupe (n.): 1680s, from French dupe "deceived person," from Middle French duppe (early 15c.), thieves' jargon, perhaps from phrase de huppe "of the hoopoe," an extravagantly crested and reputedly stupid bird.
tweet (n.): 1845, imitative of the sound made by a small bird. As a verb by 1872. Related: Tweeted; tweeting. As the word for what one does on the Twitter microblogging service, by 2007.
sanderling (n.): wading bird (Crocethia alba), c. 1600, probably from sand (n.) + diminutive suffix -ling, but OED suggests possible derivation from Old English *sand-yrðling, with second element yrðling "plowman" (literally "earthling").
Uruguay: country named for river that flows past it, which is from a native name in an extinct language, said to represent uru "bird" + guay "tail," perhaps a reference to some totemic animal. Related: Uruguayan.
fledgling: also fledgeling, 1830, "untried" (adj.), in Tennyson; 1846 as a noun meaning "young bird" (one newly fledged); from fledge + diminutive suffix -ling. Of persons, from 1856.
brooding (adj.): 1640s, "hovering, overhanging" (as a mother bird does her nest), from present participle of brood (v.); meaning "that dwells moodily" first attested 1818 (in "Frankenstein").
stuffing (n.): 1520s, "material used for filling a cushion;" 1530s, "seasoned mixture used to stuff fowls before cooking," verbal noun from stuff (v.) in the sense "fill the inside of a bird before cooking" (late 14c.).
gizzard (n.): "stomach of a bird," late 14c., from Old French gisier "entrails, giblets (of a bird)" (13c., Modern French gésier), probably from Vulgar Latin *gicerium, dissimilated from Latin gigeria (neuter plural) "cooked entrails of a fowl," a delicacy in ancient Rome, from PIE *yekwr- "liver" (see hepatitis). Parasitic -d added 1500s (perhaps on analogy of -ard words). Later extended to other animals, and, jocularly, to human beings (1660s).
peewee (adj.): 1877, "small, tiny, for children," a dialect word, possibly a varied reduplication of wee. Attested earlier (1848) as a noun meaning "a small marble." (Baseball Hall-of-Famer Harold "Peewee" Reese got his nickname because he was a marbles champion before he became a Dodgers shortstop.) As a type of bird (variously applied on different continents) it is attested from 1886, imitative of a bird cry.
distelfink (n.): Pennsylvania Dutch ornamental bird design, from German Distelfink "goldfinch," literally "thistle-finch," from Old High German distilvinko, from distil "thistle" (see thistle) + Old High German finco "finch," from PIE *(s)ping- "sparrow, finch" (see finch). The bird so called because it feeds on thistle seeds. Compare Old French chardonel "goldfinch," from chardon "thistle."
erne (n.): "sea eagle," from Old English earn "eagle," from Proto-Germanic *aron-, *arnuz "eagle" (source also of Old High German arn, German Aar, Middle Dutch arent, Old Norse örn, Gothic ara "eagle"), from PIE root *or- "great bird" (source also of Greek ornis "bird," Old Church Slavonic orilu, Lithuanian erelis, Welsh eryr "eagle"). The Germanic word also survives in the first element of names such as Arnold and Arthur.
robin (n.): common European songbird, 1540s, shortening of Robin Redbreast (mid-15c.), from masc. personal name Robin, also (in reference to the bird) in the diminutive form robinet. Redbreast alone for the bird is from early 15c., and the Robin might have been added for the alliteration. It ousted the native ruddock. In North America, the name was applied to the red-breasted thrush by 1703. Robin's egg as a shade of blue is attested from 1881.