noun
Etymology: looking (gerund of look ) (I) + glass
1.
a. : a mirror usually made of glass with a backing of some reflecting substance (as mercury)
had first seen her face in the looking glass — Jean Stafford
b. : the glass used in such a mirror
little pieces of looking glass — Leslie Thomas
2. : something held to resemble or to perform the functions of a looking glass : mirror 1b(1)