n. 1. That which is derived; anything obtained or deduced from another. [ 1913 Webster ]
2. (Gram.) A word formed from another word, by a prefix or suffix, an internal modification, or some other change; a word which takes its origin from a root. [ 1913 Webster ]
3. (Mus.) A chord, not fundamental, but obtained from another by inversion; or, vice versa, a ground tone or root implied in its harmonics in an actual chord. [ 1913 Webster ]
4. (Med.) An agent which is adapted to produce a derivation (in the medical sense). [ 1913 Webster ]
5. (Math.) A derived function; a function obtained from a given function by a certain algebraic process. [ 1913 Webster ]
☞ Except in the mode of derivation the derivative is the same as the differential coefficient. See Differential coefficient, under Differential. [ 1913 Webster ]
6. (Chem.) A substance so related to another substance by modification or partial substitution as to be regarded as derived from it; thus, the amido compounds are derivatives of ammonia, and the hydrocarbons are derivatives of methane, benzene, etc. [ 1913 Webster ]