The regular form which a substance tends to assume in solidifying, through the inherent power of cohesive attraction. It is bounded by plane surfaces, symmetrically arranged, and each species of crystal has fixed axial ratios. See Crystallization.
- A homogenous solid formed by a repeating, three-dimensional pattern of atoms, ions, or molecules and having fixed distances between constituent parts.
- The unit cell of such a pattern.
- A mineral, especially a transparent form of quartz, having a crystalline structure, often characterized by external planar faces.
- A natural or synthetic crystalline material having piezoelectric or semiconducting properties.
- An electronic device, such as an oscillator or detector, using such a material.
- A high-quality, clear, colorless glass.
- An object, especially a vessel or ornament, made of such glass.
- Such objects considered as a group.
- A clear glass or plastic protective cover for the face of a watch or clock.
- Slang A stimulant drug, usually methamphetamine, in its powdered form.
- Clear or transparent: a crystal lake; the crystal clarity of their reasoning.