Having a smooth, shiny surface or appearance like that of glass. The lake was so still that its surface appeared glassy, reflecting the sky perfectly.
Lacking liveliness or animation; expressionless. Her eyes were glassy and unfocused, indicating she was deep in thought.
Resembling glass in transparency or brittleness. The glassy ice on the pond was thin and dangerous to walk on.
(Geology) Of igneous rock or other material: having a vitreous, non-crystalline texture resembling glass. The lava cooled so quickly that it solidified into a glassy obsidian surface.