{ Caus″tic (?), Caus″tic‐al (?), } a. [L. caustucs, Ge. �, fr. � to burn. Cf. Calm, Ink.] 1. Capable of destroying the texture of anything or eating away its substance by chemical action; burning; corrosive; searing.
2. Severe; satirical; sharp; as, a caustic remark.
Caustic curve(Optics), a curve to which the ray of light, reflected or refracted by another curve, are tangents, the reflecting or refracting curve and the luminous point being in one plane. — Caustic lime. See under Lime. — Caustic potash, Caustic soda(Chem.), the solid hydroxides potash, KOH, and soda, NaOH, or solutions of the same. — Caustic silver, nitrate of silver, lunar caustic. — Caustic surface(Optics), a surface to which rays reflected or refracted by another surface are tangents. Caustic curves and surfaces are called catacaustic when formed by reflection, and diacaustic when formed by refraction.
Syn. — Stinging; cutting; pungent; searching.