derivation

A major process of word formation. In derivational modification, new words are formed which often belong to a different word class from the base form, as with truth (noun), truth-ful (adjective), false (adjective), false-hood (noun). This contrasts with inflection, a process of modification where the word class of the form is never altered, but its grammatical status is changed (eg singular to plural, present tense to past tense), as in girl/girls, talk/talked.

There are several meanings of derivation:

Look up Derivation in
Wiktionary, the free dictionary. A derivation in abstract algebra is a linear map that satisfies Leibniz' law. A derivation in calculus is defined as the instantaneous rate of change of a function. A derivation in computer science is a parse tree representing one possible way to parse a string. A derivation in linguistics is the process of changing the meaning and/or lexical class of a lexeme by adding a morpheme. A derivation in music, using the twelve tone technique, refers to the creation of a derived row, or a tone row whose entirety of twelve tones is constructed from a segment or portion of the whole, the generator.