otolith Syllabification: (o·to·lith)Pronunciation: /ˈōtlˌiTH/Definition of otolith noun Zoology each of three small oval calcareous bodies in the inner ear of vertebrates, involved in sensing gravity and movement. Derivatives otolithicPronunciation: /ˌōtlˈiTHik/ adjective otolith in other Oxford dictionaries Definition of otolith in the British & World English dictionary