two-way glass, two-way mirror

Two-way glass

A phrase that is used interchangeably with two-way mirror, “two-way” glass refers to glass that is reflective on one side and clear on the other, allowing persons on one side to see through, while people on the other see a reflection of themselves. Most people are familiar with the concept of a two-way mirror/two-way glass from Hollywood’s depiction of police dramas and the questioning room with two-way glass for observation of interrogations.

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