/ Dictionary / Index C crystal system: Meaning and Definition of Find definitions for: crys'tal sys"tem Pronunciation: [key] — Crystall. Crystall. any of the six main classifications of crystals and of crystal lattices according to their symmetry: isometric, hexagonal, tetragonal, orthorhombic, monoclinic, and triclinic. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. crystal set crystal tea Related Content Daily Word Quiz: alacrity Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language