[ fos-fer, -fawr ]
/ ˈfɒs fər, -fɔr /


any of a number of substances that exhibit luminescence when struck by light of certain wavelengths, as by ultraviolet.
Literary. a phosphorescent substance.


Archaic. phosphorescent.

Origin of phosphor

1625–35; < French phosphore < Latin Phōsphorus Phosphor

Definition for phosphor (2 of 3)


[ fos-fer, -fawr ]
/ ˈfɒs fər, -fɔr /


the morning star, especially Venus.
Also Phos·phore [fos-fawr, -fohr] /ˈfɒs fɔr, -foʊr/, Phosphorus.

Origin of Phosphor

1625–35; < Latin Phōsphorus < Greek Phōsphóros the morning star, literally, the light-bringing one, equivalent to phôs light + -phoros bringing; see -phorous

Definition for phosphor (3 of 3)


variant of phosphoro- before a vowel: phosphorate. Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for phosphor

British Dictionary definitions for phosphor


/ (ˈfɒsfə) /


a substance, such as the coating on a cathode-ray tube, capable of emitting light when irradiated with particles or electromagnetic radiation

Word Origin for phosphor

C17: from French, ultimately from Greek phōsphoros phosphorus
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Medicine definitions for phosphor



Variant ofphosphoro-
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.

Science definitions for phosphor


[ fŏsfər ]

Any of various substances that can emit light after absorbing some form of radiation. Television screens and fluorescent lamp tubes are coated on the inside with phosphors. See Note at cathode-ray tube.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.