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The symbol for the element phosphorus.
para- (often italic)
Symbol ρ The 17th letter of the Greek alphabet.
A highly reactive, poisonous nonmetallic element occurring naturally in phosphates, especially in the mineral apatite. It exists in white (or sometimes yellow), red, and black forms, and is an essential component of protoplasm. Phosphorus is used to make matches, fireworks, and fertilizers and to protect metal surfaces from corrosion. Atomic number 15; atomic weight 30.9738; melting point (white) 44.1°C; boiling point 280°C; specific gravity (white) 1.82; valence 3, 5. See Periodic Table.
Any of the various units of currency whose designations begin with ''p,'' such as the Mexican peso or the Vietnamese piastre (1966+)Related Terms