[ kaw-stik ]
/ ˈkɔ stɪk /
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See synonyms for: caustic / caustically / causticity / causticness on Thesaurus.com


capable of burning, corroding, or destroying living tissue.
severely critical or sarcastic: a caustic remark.


a caustic substance.



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On the farm, the feed for chicks is significantly different from the roosters’; ______ not even comparable.

Origin of caustic

1350–1400; Middle English <Latin causticus<Greek kaustikós burning, caustic, equivalent to kaust(ós) burnt (verbal adjective of kaíein to burn) + -ikos-ic
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2021

British Dictionary definitions for caustic

/ (ˈkɔːstɪk) /


capable of burning or corroding by chemical actioncaustic soda
sarcastic; cuttinga caustic reply
of, relating to, or denoting light that is reflected or refracted by a curved surface


Also called: caustic surface a surface that envelops the light rays reflected or refracted by a curved surface
Also called: caustic curve a curve formed by the intersection of a caustic surface with a plane
chem a caustic substance, esp an alkali
caustical, adjectivecaustically, adverbcausticity (kɔːˈstɪsɪtɪ) or causticness, noun
C14: from Latin causticus, from Greek kaustikos, from kaiein to burn
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

Medical definitions for caustic

[ kôstĭk ]


A hydroxide of a light metal.
A caustic material or substance.


Capable of burning, corroding, dissolving, or eating away by chemical action.
Of or relating to light emitted from a point source and reflected or refracted from a curved surface.
Causing a burning or stinging sensation.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
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