from
The Collaborative International Dictionary of English v.0.48
Diamine \Di*am"ine\ (?; 104), n. [Pref. di- + amine.] (Chem.)
A compound containing two amido groups united with one or
more basic or positive radicals, -- as contrasted with a
diamide.
[1913 Webster]
Note: In chemical nomenclature, if any amine or diamine is
named by prefixing the nitrogen group, the name of the
latter takes the form of amido, diamido, etc., thus
ethylene diamine, {C2H4.(NH2)2}, is also called
diamido-ethylene.
[1913 Webster]