Phosphor
Phosphor (fos"fôr or fos"for) , noun
[Compare German phosphor. See Phosphorus.]
1.
Phosphorus. [Obsolete] — Addison
2.
The planet Venus, when appearing as the morning star; Lucifer. [Poetic and Rare] — Pope
3.
A phosphorescent substance. [archaic]
4.
A substance capable of exhibiting luminescence. This term is now most commonly used to refer to substances used in fluorescent lights, image intensifiers, or cathode-ray tubes (CRT's), which luminesce when excited by ultraviolet radiation or an electron beam. In color CRT's, three different phosphors, each giving different colors when excited, are used.