DIFFRACTION

[dif.frac.tion] n [NL diffraction-, diffractio, fr. L diffringere to break apart, fr. dis- + frangere to break--more at break] (1671): a modification which light undergoes in passing by the edges of opaque bodies or through narrow slits or in being reflected from ruled surfaces and in which the rays appear to be deflected and to produce fringes of parallel light and dark or colored bands; also: a similar modification of other waves (as sound waves)