Definition of glass
(Entry 1 of 2)
1
: any of various amorphous materials formed from a melt by cooling to rigidity without crystallization: such as
a
: a usually transparent or translucent material consisting typically of a mixture of silicates
b
: a material (such as obsidian) produced by fast cooling of magma
b(1)
: an optical instrument or device that has one or more lenses and is designed to aid in the viewing of objects not readily seen
(2)
: field glasses, binoculars
—usually used in plural
c
glasses plural
: a device used to correct defects of vision or to protect the eyes that consists typically of a pair of glass or plastic lenses and the frame by which they are held in place
— called also eyeglasses, spectacles
3
: the quantity held by a glass container
4
: fiberglass
glass
verb
glassed; glassing; glasses
Definition of glass (Entry 2 of 2)
1a
: to provide with glass : glaze sense 1
b
: to enclose, case, or wall with glass
the sunroom was glassed in
2
: to make glassy
3a
: reflect
b
: to see mirrored
4
: to look at through an optical instrument (such as a pair of binoculars)
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Merriam-Webster unabridged
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Time Traveler for glass
The first known use of glass was before the 12th century
See more words from the same century