[caus.tic] adj [L causticus, fr. Gk kaustikos, fr. kaiein to burn] (14c) 1: capable of destroying or eating away by chemical action: corrosive
2: marked by incisive sarcasm
3: relating to or being the surface or curve of a caustic -- caus.ti.cal.ly adv -- caus.tic.i.ty n syn caustic, mordant, acrid, scathing mean stingingly incisive. caustic suggests a biting wit "caustic comments". mordant suggests a wit that is used with deadly effectiveness "mordant reviews of the play". acrid implies bitterness and often malevolence "acrid invective". scathing implies indignant attacks delivered with fierce severity "a scathing satire".
[2]caustic n (15c) 1: a caustic agent: as a: a substance that burns or destroys organic tissue by chemical action b: sodium hydroxide
2: the envelope of rays emanating from a point and reflected or refracted by a curved surface