a. and sb. [mod. f. Gr. κατα- back, again (as in catoptrics) + καυστικ-ός CAUSTIC. So F. catacaustique.] Catacaustic (curve); a CAUSTIC curve formed by reflexion.
1708. Kersey, Catacaustick Curve.
1721. Bailey, Catacausticks, causticks by Reflection.
1751. Chambers, Cycl., s.v. Caustic, Every curve has its twofold caustic: accordingly, caustics are divided into catacaustics and diacaustics.
1807. in G. Gregory, Dict. Arts.
