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caustic JUST WRITTEN FOR YOU

/ˈkɒstɪk/ · cas·t·ic
noun
  1. Any substance or means which, applied to animal or other organic tissue, burns, corrodes, or destroys it by chemical action; an escharotic. The caustic solution used in the laboratory was carefully handled to avoid skin contact.
  2. The envelope of reflected or refracted rays of light for a given surface or object. The caustic formed by the lens focused the light onto a small area.
  3. The envelope of reflected or refracted rays for a given curve. The mathematician studied the caustic of the parabola to understand its properties.
adjective
  1. Capable of burning, corroding or destroying organic tissue. The caustic properties of the acid made it unsuitable for use in the kitchen.
  2. Sharp, bitter, cutting, biting, and sarcastic in a scathing way. Her caustic remark about the politician's speech left a lasting impression on the audience.
Did you know? The word 'caustic' has been used in various contexts, including chemistry, optics, and linguistics, highlighting its versatility and multiple meanings.
Written by Lexi Wordsworth, Dictionary Editor 0 lookups Added Jul 15, 2026