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definitions

audio-

  1. a combining form used in the formation of compound words, with the meanings: “sound within the range of human hearing” (audiometer); “hearing” (audiology); “sound reproduction” (audiophile).

Origin of audio-

< Latin audī- (stem of audīre to hear) + -o-
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for audio-

audio-

combining form
  1. indicating hearing or soundaudiometer; audiovisual

Word Origin for audio-

from Latin audīre to hear
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
Word Origin and History for audio-

word-forming element meaning "sound, hearing," from comb. form of Latin audire "hear," (see audience); first used in English as a word-formation element 1913.

Online Etymology Dictionary, © 2010 Douglas Harper
audio- in Medicine

audio-

pref.
  1. Hearing:audiology.
  2. Sound:audiogenic.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.