Caustic

KAW-stik /ˈkɔːstɪk/
adjectiveC2GRESAT
formalliterary

Able to burn or corrode organic tissue by chemical action; (fig.) sarcastic in a scathing and bitter way.

Figuratively, 'caustic' describes language or a tone that is extremely critical, sharp, and biting, often with an acidic or corrosive effect on the recipient. It implies a harsh, often painful, form of criticism.

The story behind the word. The word 'caustic' comes from the Greek 'kaustikos', meaning 'able to burn'. This, in turn, derives from 'kaiein', meaning 'to burn'. Its original use was purely literal, describing substances that could corrode. By the 17th century, it gained its figurative sense, describing language so sharp and critical that it metaphorically 'burns' or 'corrodes' the recipient.

Word relationships

  • Sarcastic: Sarcastic describes the use of irony to mock; caustic describes the biting or scathing nature of such remarks.
  • Acrimonious: Acrimonious describes bitterness and ill-feeling, often in speech; caustic describes the sharp, burning quality of the words themselves.
  • Vitriolic: Vitriolic means filled with bitter criticism or malice; caustic implies a burning, corrosive quality.
  • Mild: Caustic is harsh and biting; mild is gentle and not severe.
  • Soothing: Caustic causes pain or irritation; soothing brings comfort.
  • Gentle: Caustic is sharp and severe; gentle is soft and kind.

Word family

  • caustically (adverb): in a caustic manner
  • causticity (noun): the quality of being caustic

Collocations

  • caustic remarks
  • caustic wit
  • caustic humor
  • caustic criticism
  • caustic substance

Example sentences

  • "The film critic's caustic remarks about the acting and plot left the director feeling utterly demoralized." Describing a critic's review.
  • "Handle the concentrated acid with extreme care, as it is a highly caustic substance that can cause severe burns." Referring to a chemical substance.

Memory hook

Think of 'CAUS-TIC' as causing a 'tick' (a sharp, painful sensation) with biting words, like a 'caustic' chemical. Causes a tick, burns

When not to use

Do not use 'caustic' for mild criticism or gentle humor. It implies a severe, often hurtful, level of sharpness. Also, be aware of its literal chemical meaning.

Fun facts

  • Lye (sodium hydroxide) is a common example of a caustic substance.
  • The figurative use of 'caustic' is an excellent example of how language borrows from physical properties to describe abstract concepts like tone and criticism.

Related words

Sarcasm, Lampoon, Critique

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