Entry 1 sense Webster, 1913 Paleozoölogy /(pā`lē̇*ō̇*zō̇*ŏl"ō̇*jy̆)/ · Pa·le·o·zo·öl·o·gy · IPA 01 n. The science of extinct animals, a branch of paleontology. 1. The science of extinct animals, a branch of paleontology.