otolith

oto·lith

noun \ˈōt-^əl-ˌith\

Definition of OTOLITH

: a calcareous concretion in the inner ear of a vertebrate or in the otocyst of an invertebrate that is especially conspicuous in many bony fishes where it forms a hard body and in most of the higher vertebrates where it is represented by a mass of small calcareous otoconia—called also statolith

—oto·lith·ic \ˌōt-^əl-ˈith-ik\ adjective