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definitions

oxy-

1
  1. a combining form meaning “sharp,” “acute,” “keen,” “pointed,” “acid,” used in the formation of compound words: oxycephalic; oxygen; oxymoron.

Origin of oxy-

1
< Greek, combining form of oxýs sharp, keen, acid

oxy-

2
  1. a combining form representing oxygen in compound words, sometimes as an equivalent of hydroxy-: oxychloride.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for oxy-

oxy-

1
combining form
  1. denoting something sharp; acuteoxytone

Word Origin for oxy-

from Greek, from oxus

oxy-

2
combining form
  1. containing or using oxygenoxyacetylene
  2. a former equivalent of hydroxy-
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 oxy-

word-forming element meaning "sharp, pointed; acid," from Greek oxy-, comb. form of oxys "sharp, pungent" (see acrid). Also used as a comb. form of oxygen.

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

oxy-

pref.
  1. Oxygen, especially additional oxygen:oxygenation.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.