Use the adjective caustic to describe any chemical that is able to burn living tissue or other substances, or, figuratively, a statement that has a similarly burning effect. Caustic in this sense means harshly critical.

In the chemical sense, a near synonym is corrosive. In the figurative sense, near synonyms are biting, scathing, and sarcastic. The source of the word caustic is Latin causticus, from Greek kaustikos, from kaiein "to burn."

Definitions of caustic
  1. adjective
    of a substance, especially a strong acid; capable of destroying or eating away by chemical action
    synonyms: corrosive, erosive, mordant, vitriolic
    causing destruction or much damage
  2. adjective
    harsh or corrosive in tone
    caustic jokes about political assassination, talk-show hosts and medical ethics”
    synonyms: acerb, acerbic, acid, acrid, astringent, bitter, blistering, sulfurous, sulphurous, virulent, vitriolic
    disagreeable to the senses, to the mind, or feelings
  3. noun
    any chemical substance that burns or destroys living tissue
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    a strong solution of sodium or potassium hydroxide
    silver nitrate
    a nitrate used in making photographic emulsions; also used in medicine as a cautery and as a topical antibacterial agent
    caustic potash, potash, potassium hydroxide
    a potassium compound often used in agriculture and industry
    lunar caustic
    silver nitrate fused into sticks and formerly used as a caustic
    caustic soda, sodium hydroxide
    a strongly alkaline caustic used in manufacturing soap and paper and aluminum and various sodium compounds
    type of:
    chemical compound, compound
    (chemistry) a substance formed by chemical union of two or more elements or ingredients in definite proportion by weight
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