diazo-

from The Century Dictionary.

• noun In chem., a prefix signifying that a compound contains a group consisting of phenyl (C₆H₅) united with a radical consisting of two nitrogen atoms.

from the GNU version of the Collaborative International Dictionary of English.

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

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• adjective relating to or containing diazonium