P P /ˈpiː/

noun

1. The 16th letter of the Roman alphabet  ( P )
   the 16th letter of the Roman alphabet
   
2. A multivalent nonmetallic element of the nitrogen family that occurs commonly in inorganic phosphate rocks and as organic phosphates in all living cells; is highly reactive and occurs in several allotropic forms  ( atomic number 15 , P , phosphorus )
   a multivalent nonmetallic element of the nitrogen family that occurs commonly in inorganic phosphate rocks and as organic phosphates in all living cells; is highly reactive and occurs in several allotropic forms