crystal

noun

• 1a piece of a homogeneous solid substance having a natural geometrically regular form with symmetrically arranged plane faces: a quartz crystal ice crystals formed where his breath froze
• Chemistry any solid consisting of a symmetrical, ordered, three-dimensional aggregation of atoms or molecules.
• Electronics a crystalline piece of semiconductor used as an oscillator or transducer.
• [mass noun] a clear transparent mineral, especially quartz: cups cut from crystal
• a piece of crystalline substance believed to have healing powers.

• 2 (also crystal glass) [mass noun] highly transparent glass with a high refractive index: [as modifier]:a crystal chandelier
• articles made of crystal glass:a collection of crystal
• [count noun] the glass over a watch face.

• 3 [as modifier] clear and transparent like crystal:the clean crystal waters of the lake