Crystal is defined as a mineral that is generally made of transparent quartz in a shape of cubic symmetry or a glass that is clear, colorless and of high quality.(noun)
The definition of crystal is clear or see through.(adjective)
An example of crystal used as an adjective is the phrase "crystal lake" which means a lake where there is no garbage, pollution, etc. ruining the color or clarity of the water.
See crystal in Webster's New World College Dictionary
Origin: altered (modeled on L) < ME & OFr cristal, OE cristalla < L crystallum, crystal, ice < Gr krystallos < kryos: see crude
Origin: see crystal
See crystal in American Heritage Dictionary 4
Origin: Middle English cristal, from Old French, from Latin crystallum, from Greek krustallos, ice, crystal; see kreus- in Indo-European roots.
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