Definition of: phosphorus

(fos′fər·əs) noun
1. A widely distributed nonmetallic element (symbol P, atomic number 15) existing in several allotropie forms, including red phosphorus and the more common white phosphorus, a yellowish, waxy, exceedingly poisonous solid that ignites spontaneously in air. See PERIODIC TABLE.
2. Any phosphorescent substance. [<NL <L Phosphorus the morning star <Gk. phōsphoros (astēr), lit., light-bringing <phōs a light + phoros bearing <pherein bear]