Webster's English Dictionary

Enter the word to look up:

diffraction

dif.frac.tion \-'rak-sh*n\ n [NL diffraction-, diffractio, fr. L 
   diffractus, pp. of dif]fringere to break apart, fr. dis- + frangere to 
   break  more at BREAK : a modification which light undergoes in passing by 
   the edges of opaque b odies or through narrow slits or in being reflected 
   from ruled surfaces and in which the rays appear to be deflected and 
   produce fringes of parallel light and dark or colored bands; also : a 
   similar modification of other waves