Allotropism

2 definitions found

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

  Allotropism \Al*lot"ro*pism\, Allotropy \Al*lot"ro*py\, n. [Gr.
     ? other + direction, way, ? to turn: cf. F. allotropie.]
     (Chem.)
     The property of existing in two or more conditions which are
     distinct in their physical or chemical relations.
     [1913 Webster]


  
     Note: Thus, carbon occurs crystallized in octahedrons and
           other related forms, in a state of extreme hardness, in
           the diamond; it occurs in hexagonal forms, and of
           little hardness, in black lead; and again occurs in a
           third form, with entire softness, in lampblack and
           charcoal. In some cases, one of these is peculiarly an
           active state, and the other a passive one. Thus, ozone
           is an active state of oxygen, and is distinct from
           ordinary oxygen, which is the element in its passive
           state.
           [1913 Webster]

From WordNet (r) 2.0 [wn]:

  allotropism
       n : the phenomenon of an element existing in two or more
           physical forms [syn: {allotropy}]