Phosphori

1 definition found

From The Collaborative International Dictionary of English v.0.48 [gcide]:

  Phosphorus \Phos"phor*us\ (f[o^]s"f[o^]r*[u^]s), n.; pl.
     {Phosphori} (f[o^]s"f[o^]r*[imac]). [L., the morning star,
     Gr. fwsfo`ros, lit., light bringer; fw^s light + fe`rein to
     bring.]
     1. The morning star; Phosphor.
        [1913 Webster]


  
     2. (Chem.) A poisonous nonmetallic element of the nitrogen
        group, obtained as a white, or yellowish, translucent waxy
        substance, having a characteristic disagreeable smell;
        this waxy allotropic form is also called {yellow
        phosphorus}, to distinguish it from another allotropic
        form, {red phosphorus}. 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 combined, 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. It is an essential component of the
        genetic material of all living organisms. The molecule
        contains four atoms. Symbol P. Atomic weight 31.0.
        [1913 Webster]
  
     3. (Chem.) Hence, any substance which shines in the dark like
        phosphorus, as certain phosphorescent bodies.
        [1913 Webster]
  
     {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 phosphorus}, 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.
  
     {yellow phosphorus} (Chem.), the waxy yellow allotropic form
        of elemental phosphorus. See also {phosphorus}[2].
        [1913 Webster +PJC]