noun, phos·pho·rus often attributive \ˈfäs-f(ə-)rəs\

chemistry : a poisonous chemical element that glows in the dark and burns when it is touched by air

Full Definition of PHOSPHORUS

:  a phosphorescent substance or body; especially :  one that shines or glows in the dark
also phos·pho·rous \same\ :  a nonmetallic element of the nitrogen family that occurs widely especially as phosphates — see element table


New Latin, from Greek phōsphoros light-bearing — more at phosphor
First Known Use: 1645
PHOSPHORUS Defined for Kids


noun phos·pho·rus \ˈfäs-fə-rəs\

Definition of PHOSPHORUS for Kids

:  a white or yellowish waxy chemical element that gives a faint glow in moist air
Medical Dictionary


noun , phos·pho·rus often attrib \ˈfäs-f(ə-)rəs\

Medical Definition of PHOSPHORUS

:  a nonmetallic multivalent element that occurs widely in combined form especially as inorganic phosphates in minerals, soils, natural waters, bones, and teeth and as organic phosphates in all living cells and that exists in several allotropic forms—symbol P; see element table
July 01, 2015
precarious Hear it
not certain, secure, or steady
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