earstone

/ˈɪrˌstoʊn/
noun
  1. A small, hard structure inside the inner ear of vertebrates that helps with balance and hearing; also called an otolith.
    • Scientists study earstones to learn about the hearing abilities of ancient animals.
    • The fish's earstone can be examined to determine its age.
    • A damaged earstone can cause a person to feel dizzy or lose their balance.
Synonyms
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