The Collaborative International Dictionary
anacamptics
Catoptrics \Ca*top"trics\, n. [Cf. F. catoptrique. See Catropric.] (Physics) That part of optics which explains the properties and phenomena of reflected light, and particularly that which is reflected from mirrors or polished bodies; -- formerly called anacamptics.
Wiktionary
anacamptics
n. 1 The science of reflected light; catoptrics. 2 The science of reflected sounds.