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Definition of phosphorus - 8 dictionary results

phos⋅pho⋅rus

[fos-fer-uhs]
–noun, plural -pho⋅ri [-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.

Origin:
1620–30; < NL phōsphorus phosphorus; L: morning star; see Phosphor

Phos⋅pho⋅rus

[fos-fer-uhs]
–noun
Phosphor.

Phos⋅phor

[fos-fer, -fawr]
–noun
the morning star, esp. Venus.
Also, Phos⋅phore [fos-fawr, -fohr] , Phosphorus.


Origin:
1625–35; < L Phōsphorus < Gk Phōsphóros the morning star, lit., the light-bringing one, equiv. to phôs light + -phoros bringing; see -phorous
phos·pho·rus   (fŏs'fər-əs)   
n.  
  1. Symbol P A highly reactive, poisonous, nonmetallic element occurring naturally in phosphates, especially apatite, and existing in three allotropic forms, white (or sometimes yellow), red, and black. An essential constituent of protoplasm, it is used in safety matches, pyrotechnics, incendiary shells, 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 Table at element.
  2. A phosphorescent substance.

[Latin Phōsphorus, morning star, from Greek phōsphoros, bringing light, morning star : phōs, light; see bhā-1 in Indo-European roots + -phoros, -phorous.]

Phosphorus

Phos"phor*us\, n.; pl. Phosphori. [L., the morning star, Gr. ?, lit., light bringer; ? light + ? to bring.]

1. The morning star; Phosphor.

2. (Chem.) A poisonous nonmetallic element of the nitrogen group, obtained as a white, or yellowish, translucent waxy substance, having a characteristic disagreeable smell. It is very active chemically, must be preserved under water, and unites with oxygen even at ordinary temperatures, giving a faint glow, -- whence its name. It always occurs compined, usually in phosphates, as in the mineral apatite, in bones, etc. It is used in the composition on the tips of friction matches, and for many other purposes. The molecule contains four atoms. Symbol P. Atomic weight 31.0.

3. (Chem.) Hence, any substance which shines in the dark like phosphorus, as certain phosphorescent bodies.

Bologna phosphorus (Chem.), sulphide of barium, which shines in the dark after exposure to light; -- so called because this property was discovered by a resident of Bologna. The term is sometimes applied to other compounds having similar properties.

Metallic phosphorus (Chem.), an allotropic modification of phosphorus, obtained as a gray metallic crystalline substance, having very inert chemical properties. It is obtained by heating ordinary phosphorus in a closed vessel at a high temperature.

Phosphorus disease (Med.), a disease common among workers in phosphorus, giving rise to necrosis of the jawbone, and other symptoms.

Red, or Amorphous, phosphorus (Chem.), an allotropic modification of phosphorus, obtained as a dark red powder by heating ordinary phosphorus in closed vessels. It is not poisonous, is not phosphorescent, and is only moderately active chemically. It is valuable as a chemical reagent, and is used in the composition of the friction surface on which safety matches are ignited.

Solar phosphori (Chem.), phosphorescent substances which shine in the dark after exposure to the sunlight or other intense light.

Main Entry: phos·pho·rus
Pronunciation: 'fäs-f(&-)r&s
Function: noun
often attributive : a nonmetallic multivalent elementthat 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 severalallotropic forms —symbol P; —see ELEMENT table

phosphorus phos·pho·rus (fŏs'fər-əs)
n.
Symbol P

  1. 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.
  2. A phosphorescent substance.

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.
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