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.

&fist; 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.