one-way mirror
noun
a sheet of glass that can be seen through from one side and is a mirror on the other, used especially for observation of criminal suspects by law-enforcement officials or witnesses.
Also called two-way mirror.
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Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
two-way mirror
noun
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
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