word-forming element meaning "egg, eggs," from Greek ōon "egg," cognate with Latin ovum, Old Norse egg,from PIE *ōwyo‑, *ōyyo‑ "egg," which perhaps is a derivative of the root *awi- "bird."
Entries linking to oo-
*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."
oocyst n.
in biology, "sac or pouch serving as a receptacle for eggs," 1875; see oo- "egg" + cyst.