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internal ear

noun
  1. the inner portion of the ear, involved in hearing and balance, consisting of a bony labyrinth that is composed of a vestibule, semicircular canals, and a cochlea and that encloses a membranous labyrinth.Compare ear1(def 1).
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

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British Dictionary definitions for internal ear

internal ear

noun
  1. the part of the ear that consists of the cochlea, vestibule, and semicircular canalsAlso called: inner ear, labyrinth
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
internal ear in Medicine

internal ear

n.
  1. inner ear
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.