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definitions

aero-

  1. a combining form meaning “air,” used in formation of compound words: aerodrome.
Also aer-, aeri-.

Origin of aero-

< Greek, equivalent to āer- (stem of āḗr air1) + -o- -o-
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for aero-

aero-

aeri- or before a vowel aer-

combining form
  1. denoting air, atmosphere, or gasaerodynamics
  2. denoting aircraftaeronautics

Word Origin for aero-

ultimately from Greek aēr air
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 aero-

word-forming element meaning "air, atmosphere; aircraft; gasses," from Greek aero-, comb. form of aer (genitive aeros) "air, lower atmosphere" (see air (n.1)).

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

aero-

pref.
  1. Air; atmosphere:aerobic.
  2. Gas:aerosol.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.