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.
DIAZO-
Meaning of DIAZO- in English
Webster's Revised Unabridged English Dictionary. Пересмотренный полный словарь английского языка Webster. 2012