derivation (n.)
A term used in MORPHOLOGY to refer to one of the two main categories or processes of WORD-FORMATION (derivational morphology), the other being INFLECTION(AL); also sometimes called derivatology. These terms also apply to the two types of AFFIX involved in word-formation. Basically, the result of a derivational process is a new word (e.g. nation ⇒ national), whereas the result of an inflectional (or non-derivational) process is a different form of the same word (e.g. nations, nationals). The distinction is not totally clear-cut, however (e.g. how best to analyze -ly in English). Derivational affixes change the grammatical CLASS of MORPHEMES to which they are attached (as in SUFFIXATION, e.g. -tion is a noun-forming derivational suffix); they also usually occur closer to the ROOT morpheme than do inflections, e.g. nation-al-ize + -ing/-s/-d. Often they have independently stateable LEXICAL MEANINGS (e.g. mini-, sub-), though these are not always easy to identify (e.g. -er). The combination of root and derivational affixes is usually referred to as the STEM of the word, i.e. the ELEMENT to which inflections are attached; several modes of classification are available in the literature on this subject.
In GENERATIVE GRAMMAR, derivation refers to the set of formally identifiable stages used in generating a SENTENCE from an INITIAL SYMBOL to a TERMINAL STRING, i.e. the whole set of PHRASE-STRUCTURE, TRANSFORMATIONAL, etc., RULES which have applied. In a more restricted context, a derived structure refers to the form of an output PHRASE-MARKER, after a transformational rule has applied.
In HISTORICAL LINGUISTICS, derivation is used to refer to the origins or historical development of a LANGUAGE or linguistic form. Sounds, words and structures are said to be derived from corresponding FORMS in an earlier state of a language.
