Definition of "crystal set" []

• An early radio receiver using a crystal detector. (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.

• "    It looked like a parody of a human skull, with a batlike face, and cold, impassive eyes of colored crystal set in the unfamiliar blue-tinted metal."