a clear, transparent mineral or glass resembling ice.

the transparent form of crystallized quartz.

Chemistry, Mineralogy . a solid body having a characteristic internal structure and enclosed by symmetrically arranged plane surfaces, intersecting at definite and characteristic angles.

anything made of or resembling such a substance.

a single grain or mass of a crystalline substance.

glass of fine quality and a high degree of brilliance.

articles, esp. glassware for the table and ornamental objects, made of such a glass.

the glass or plastic cover over the face of a watch.

Radio .

the piece of germanium, silicon, galena, or the like forming the essential part of a crystal detector.

the crystal detector itself.

Electronics . a quartz crystal ground in the shape of a rectangular parallelepiped, which vibrates strongly at one frequency when electric voltages of that frequency are placed across opposite sides

used to control the frequency of an oscillator (crystal oscillator), as of a radio transmitter.

Slang . any stimulant drug in powder form, as methamphetamine or PCP.

composed of crystal.

resembling crystal; clear; transparent.

Radio . pertaining to or employing a crystal detector.

indicating the fifteenth event of a series, as a wedding anniversary.

to make into crystal; crystallize.

to cover or coat with, or as if with, crystal (usually fol. by over ).

adjective

clouded , foggy

adjective

clear-cut , limpid , lucent , lucid , luminous , pellucid , translucent , transpicuous , unblurrednotes:crystal from greek krustallos , originally meant \'ice\' and it is , properly , rock crystal - describing ornamental pieces or items of crystallized quartz; fine glass , when cut or etched , is called crystal - but often there is no crystallized quartz but rather lead and it is properly called lead crystal , clear , crystalline , diamond , glass , hard , ice , mineral , oscillator , quartz , transparent , unblurred