ENGLISH
REFERENCE

glass

n. C / U
A1 Beginner Oxford US //ˈɡɫæs// UK //ɡlˈɑːs// glass Archaic General-service Informal

n. a hard, clear material that you can see through. It is used to make things like windows, bottles, and mirrors.

n. a hard, brittle, and typically transparent or translucent substance produced by fusing sand with soda and lime. Often used metonymically to refer to objects made from the material, such as drinking vessels or lenses.


SIMPLE

Be careful not to break the glass window.

CONTEXTUAL

The architect chose to use recycled glass for the building's large front windows to let in more natural light.

COMPLEX

Modern skyscrapers utilize specialized glass treated with metallic oxides to reflect solar radiation, significantly reducing the energy required for internal climate control during the summer months.

Synonyms
Usage

Uncountable when referring to the material itself; countable when referring to a drinking container or a specific lens.

Idioms4 entries

© 2026 English Reference