- 1[countable] a small piece of a substance with many even sides, that is formed naturally when the substance becomes solid ice/salt crystals
- 2[uncountable, countable] a clear mineral, such as quartz, used in making jewelry and decorative objects a pair of crystal earrings
- 3[uncountable] glass of very high quality a crystal chandelier/vase Every table had been set with fine china and crystal.
- 4 [countable] a piece of glass or plastic that covers the face of a watch see also liquid crystal display
- 5= meth