"large cage or building where birds are reared or kept," 1570s, from Latin aviarium "place in which birds are kept," neuter of aviarius "of birds," from avis "bird" (from PIE root *awi- "bird").
Entries linking to aviary
*awi-
Proto-Indo-European root meaning "bird." It also might be the source of *woyo, *oyyo, Proto-Indo-European words for "egg."
It forms all or part of: auspex; auspices; auspicious; avian; aviary; aviation; aviator; avicide; aviculture; aviform; caviar; cockney; egg (n.); ocarina; oo-; oocyte; oolite; oology; osprey; ostrich; oval; ovary; ovate (adj.); oviform; oviparous; ovoviviparous; ovoid; ovulate; ovulation; ovule; ovum.
It is the hypothetical source of/evidence for its existence is provided by: Sanskrit vih, Avestan vish, Latin avis "bird;" Greek aietos "eagle;" Old Church Slavonic aja, Russian jajco, Breton ui, Welsh wy, Greek ōon, Latin ovum, Old Norse egg, Old High German ei, Gothic ada all meaning "egg."
rara avis n.
c. 1600, "peculiar person, person of a type seldom encountered," 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. A phrase used of Horace's peacock (a Roman delicacy), Juvenal's black swan ("Rara avis in terris, nigroque simillima cygno"). A figure perhaps natural to the superstitious Romans, who divined by bird-watching.