the GNU version of the Collaborative International Dictionary of English
n. Any compound containing two amido groups united with one or more acid or negative radicals, -- as distinguished from a diamine. Cf. Amido acid, under amido, and Acid amide, under amide.
The Century Dictionary and Cyclopedia
n. Same as hydrazine.
n. The name of a class of organic compounds containing two univalent amido groups, -CONH; they are derived from dibasic acids.
Word Usage
"Urea (carbonyl diamide) is a fertilizer that is sometimes used to melt ice."