[fos-fer-uh
s] 
[-fuh-rahy] . | 1. | Chemistry. a solid, nonmetallic element existing in at least three allotropic forms, one that is yellow, poisonous, flammable, and luminous in the dark, one that is red, less poisonous, and less flammable, and another that is black, insoluble in most solvents, and the least flammable. The element is used in forming smoke screens, its compounds are used in matches and phosphate fertilizers, and it is a necessary constituent of plant and animal life in bones, nerves, and embryos. Symbol: P; atomic weight: 30.974; atomic number: 15; specific gravity: (yellow) 1.82 at 20°C, (red) 2.20 at 20°C, (black) 2.25–2.69 at 20°C. |
| 2. | any phosphorescent substance. |
| 3. | phosphor. |
[fos-fer, -fawr] | the morning star, esp. Venus. |
| phos·pho·rus (fŏs'fər-əs) n.
[Latin Phōsphorus, morning star, from Greek phōsphoros, bringing light, morning star : phōs, light; see bhā-1 in Indo-European roots + -phoros, -phorous.] |
phosphorus phos·pho·rus (fŏs'fər-əs)
n.
Symbol P
A highly reactive poisonous nonmetallic element occurring naturally in phosphates, especially apatite, and an essential constituent of protoplasm. 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.
A phosphorescent substance.
| phosphor (fŏs'fər) Pronunciation Key
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. |
| phosphorus (fŏs'fər-əs) Pronunciation Key
Symbol P 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. |