Entry 1 sense Webster, 1913 Oology /ō(w)ŏ′ləjē/ · O·ol·o·gy · IPA /oʊ̯ˈ(w)ɑləd͡ʒi/ 01 n. The science of eggs in relation to their coloring, size, shape, and number. 1. The science of eggs in relation to their coloring, size, shape, and number.