Diazo- \Di*az"o-\ [Pref. di- + azo-] (Chem.) A combining form (also used adjectively), meaning pertaining to, or derived from, a series of compounds containing a radical of two nitrogen atoms, united usually to an aromatic radical; as, diazo-benzene, C6H5.N2.OH. [1913 Webster]

Note: Diazo compounds are in general unstable, but are of great importance in recent organic chemistry. They are obtained by a partial reduction of the salts of certain amido compounds. [1913 Webster]

Diazo reactions (Chem.), a series of reactions whereby diazo compounds are employed in substitution. These reactions are of great importance in organic chemistry. [1913 Webster]

Source: The Collaborative International Dictionary of English v.0.48
 

diazo adj : relating to or containing diazonium [also: diazoes (pl)]

Source: WordNet (r) 2.0
 

Diazo- \Di*az"o-\ [Pref. di- + azo-] (Chem.) A combining form (also used adjectively), meaning pertaining to, or derived from, a series of compounds containing a radical of two nitrogen atoms, united usually to an aromatic radical; as, diazo-benzene, C6H5.N2.OH.

Note: Diazo compounds are in general unstable, but are of great importance in recent organic chemistry. They are obtained by a partial reduction of the salts of certain amido compounds.

Diazo reactions (Chem.), a series of reactions whereby diazo compounds are employed in substitution. These reactions are of great importance in organic chemistry.

Source: Webster's Revised Unabridged Dictionary (1913)