Caustic

Friday, September 5, 2025
Word of the Day

What is Caustic?

adjective
Able to burn or corrode; severely sarcastic or scathing in tone.

Pronunciation

US pronunciation: /ˈkɑː.stɪk/
UK pronunciation: /ˈkɔː.stɪk/
Slow pronunciation: KAW-stik

Meaning Explained

Caustic refers literally to substances that eat away or corrode, and figuratively to speech or wit so sharp it sears. It’s a word of fire, acid, and ruthless precision.

Why This Word?

Chosen to highlight the power of words and reactions — chemical or rhetorical — that leave lasting marks.

Examples of Use

Here's how this word appears in everyday language:

  • The scientist handled the caustic solution with extreme caution.
  • His caustic wit often amused friends but alienated strangers.
  • The critic’s caustic review nearly ended the playwright’s career.

Word Origins

Latin causticus, from Greek kaustikos, “capable of burning”

Originally used in medicine and chemistry; later adopted into literature for biting satire and criticism.

First appearance in English: 14th century

Word Family

Related forms of this word:

  • Noun: causticity

    Her causticity made her both admired and feared.

  • Adjective: acerbic

    He had an acerbic style of commentary.

  • Adjective: biting

    She delivered a biting critique of the proposal.

Around the World

How this word appears in other languages:

  • Spanish: cáustico
  • French: caustique
  • German: ätzend
  • Italian: caustico
  • Portuguese: cáustico

If you Already Know This Word

If you've mastered this word, try these more advanced alternatives:

Sarcastic

“Sarcastic” can be playful or light; “caustic” is corrosive and often damaging.

Acerbic

“Acerbic” is sharp and sour; “caustic” suggests burning intensity.

Scathing

“Scathing” is severely critical; “caustic” implies both literal and figurative burning.

Fun Facts

  • The phrase “caustic wit” became especially popular in 20th-century American criticism.
  • Caustic substances were once used in medicine to cauterize wounds — literally burning to heal.

Cultural Usage

  • Oscar Wilde and Dorothy Parker were famed for their caustic humor.
  • In chemistry, caustic soda (sodium hydroxide) is a powerful base used in industry.

Common Mistakes

Often confused with “sarcastic”; “caustic” is harsher, corrosive, and damaging.

Micro Story

Her caustic remarks left the room in uneasy silence.