[ kaw-stik ]
See synonyms for: causticcausticallycausticitycausticness on

  1. capable of burning, corroding, or destroying living tissue.

  2. severely critical or sarcastic: a caustic remark.

  1. a caustic substance.

  2. Optics.

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

Other words for caustic

Other words from caustic

  • caus·ti·cal·ly, caus·tic·ly, adverb
  • caus·tic·i·ty [kaw-stis-i-tee], /kɔˈstɪs ɪ ti/, caus·tic·ness, noun
  • non·caus·tic, adjective
  • non·caus·ti·cal·ly, adverb
  • o·ver·caus·tic, adjective
  • o·ver·caus·ti·cal·ly, adverb
  • o·ver·caus·tic·i·ty, noun
  • un·caus·tic, adjective
  • un·caus·ti·cal·ly, adverb Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use caustic in a sentence

British Dictionary definitions for caustic


/ (ˈkɔːstɪk) /

  1. capable of burning or corroding by chemical action: caustic soda

  2. sarcastic; cutting: a caustic reply

  1. of, relating to, or denoting light that is reflected or refracted by a curved surface

  1. Also called: caustic surface a surface that envelops the light rays reflected or refracted by a curved surface

  2. Also called: caustic curve a curve formed by the intersection of a caustic surface with a plane

  1. chem a caustic substance, esp an alkali

Origin of caustic

C14: from Latin causticus, from Greek kaustikos, from kaiein to burn

Derived forms of caustic

  • caustical, adjective
  • caustically, adverb
  • causticity (kɔːˈstɪsɪtɪ) or causticness, noun

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