The Collaborative International Dictionary of English v.0.48:

Catacaustic \Cat`a*caus"tic\, n. (Physics)
   A caustic curve formed by reflection of light. --Nichol.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Catacaustic \Cat`a*caus"tic\, a. [Pref. cata + caustic.]
   (Physics)
   Relating to, or having the properties of, a caustic curve
   formed by reflection. See Caustic, a. --Nichol.
   [1913 Webster]