Definition of "crystal" []

• A homogenous solid formed by a repeating, three-dimensional pattern of atoms, ions, or molecules and having fixed distances between constituent parts. (noun)
• The unit cell of such a pattern. (noun)
• A mineral, especially a transparent form of quartz, having a crystalline structure, often characterized by external planar faces. (noun)
• A natural or synthetic crystalline material having piezoelectric or semiconducting properties. (noun)
• An electronic device, such as an oscillator or detector, using such a material. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "Q: Am I the only passenger whose primary reference for the term crystal ship is the song about heroin by the Doors?"
• "In short the crystal is all about the exterior form, not about the displays or the experience inside the building."
• "Another commercial has a dumb office worker with a glass snow globe, which he calls his crystal ball."