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The Collaborative International Dictionary of English v.0.48 (gcide)

Nitrogen \Ni`tro*gen\ (n[imac]"tr[-o]*j[e^]n), n. [L. nitrum
natron -gen: cf. F. nitrog[`e]ne. See {Niter}.] (Chem.)
A colorless nonmetallic element of atomic number 7, tasteless
and odorless, comprising four fifths of the atmosphere by
volume in the form of molecular nitrogen ({N2}). It is
chemically very inert in the free state, and as such is
incapable of supporting life (hence the name {azote} still
used by French chemists); but it forms many important
compounds, such as ammonia, nitric acid, the cyanides, etc,
and is a constituent of all organized living tissues, animal
or vegetable. Symbol N. Atomic weight 14.007. It was formerly
regarded as a permanent noncondensible gas, but was liquefied
in 1877 by Cailletet of Paris, and Pictet of Geneva, and
boils at -195.8 [deg] C at atmospheric pressure. Liquid
nitrogen is used as a refrigerant to store delicate
materials, such as bacteria, cells, and other biological
materials.
[1913 Webster PJC]