Caustic
adj, noun, slang ·Common ·High school level
Definitions
- 1 Any substance or means which, applied to animal or other organic tissue, burns, corrodes, or destroys it by chemical action; an escharotic. countable, uncountable
"The association of the heavenly bodies with known metals and also with human organs and destinies goes back to ancient Chaldea, the land of astrologers. In Chaucer’s words: ‘The seven bodies eek, lo hear anon. Sol gold is, and Luna silver we declare; Mars yron, Mercurie is quyksilver; Saturnian leed; and Jubitur is tyn, and Venus coper, by my fathers kyn.’ […] Corresponding names were bestowed upon salts of these metals by the alchemists, and some of them have persisted down to the present day. Some examples are lunar caustic (silver nitrate); vitriol of Venus (copper sulphate); sugar of Saturn (lead acetate); and vitriol of Mars, or Martial vitriol (ferrous sulphate)."
- 2 the envelope of light rays reflected or refracted by a curved surface or object wordnet
- 3 The envelope of reflected or refracted rays of light for a given surface or object. countable, uncountable
- 4 any chemical substance that burns or destroys living tissue wordnet
- 5 The envelope of reflected or refracted rays for a given curve. countable, uncountable
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- 6 Caustic soda. informal, uncountable
- 1 Capable of burning, corroding or destroying organic tissue.
- 2 Sharp, bitter, cutting, biting, and sarcastic in a scathing way. usually
""How now!" said Scrooge, caustic and cold as ever."
- 1 of a substance, especially a strong acid; capable of destroying or eating away by chemical action wordnet
- 2 harsh or corrosive in tone wordnet
Example
More examples"Though common in cleaning products, ammonia is caustic."
Etymology
From the Latin causticus (“burning”), from Ancient Greek καυστικός (kaustikós, “burning”), from καυστός (kaustós, “burnt”) + -ικός (-ikós).
Related phrases
More for "caustic"
Data sourced from Wiktionary, WordNet, CMU, and other open linguistic databases. Updated March 2026.