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One of a class of strongly basic substances derived from ammonia by replacement of one or more hydrogen atoms by a basic atom or radical.

One of a class of strongly basic substances derived from ammonia by replacement of one or more hydrogen atoms by a basic atom or radical.

A substance which may be derived from ammonia by the replacement of one or more of the hydrogen atoms by hydrocarbon radicals; the substitution of one hydrogen atom constitutes a primary, that of two atoms a secondary, and that of three a tertiary amine.

[Greek] A nitrogen compound formed in plants, also produced by bacterial action on amino acids, a derivative from ammonia by hydrogen replacement.