What does "incandescent" mean?

Incandescent: White, glowing, or luminous, with intense heat; as, incandescent carbon or platinum; hence, clear; shining; brilliant. Holy Scripture become resplendent; or, as one might say, incandescent throughout. I. Taylor. Incandescent lamp or light (Elec.), a kind of lamp in which the light is produced by a thin filament of conducting material, usually carbon, contained in a vacuum, and heated to incandescence by an electric current, as in the Edison lamp; -- called also incandescence lamp, and glowlamp.