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caus·tic

(kôstĭk)

adj.

1. Capable of burning, corroding, dissolving, or eating away by chemical action.

2. Sarcastic or cutting; biting: “The caustic jokes ... deal with such diverse matters as political assassination, talk-show hosts, medical ethics” (Frank Rich).

3. Given to making caustic remarks: a caustic TV commentator.

1. A caustic material or substance.

2. A hydroxide of a light metal.

3. The enveloping pattern formed by light rays reflecting or refracting from a curved surface.

[Middle English caustik, from Latin causticus, from Greek kaustikos, from kaustos, from kaiein, kau-, to burn.]

causti·cal·ly adv.

caus·tici·ty (kô-stĭsĭ-tē) n.

Indo-European & Semitic Roots Appendices

Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

Indo-European Roots

Semitic Roots

The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.

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