Longman Dictionary of

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underlying form. For example, in French one can derive a form such as
[bõ] bon (“good”) from an underlying form /bon/ by means of two rules,
one of which nasalizes a vowel before a nasal consonant, the second of
which deletes a syllable-final nasal consonant.
in MORPHOLOGY and WORD FORMATION, the formation of new words by
adding AFFIXES to other words or morphemes. For example, the noun
insanity is derived from the adjective sane by the addition of the negative
prefix in- and the noun-forming suffix –ity. Derivation typically results in
changes of PARTS OFSPEECH. It can be contrasted with INFLECTION, which
never changes the lexical category.
in SYNTAX, the process of applying grammatical rules to underlying forms,
for example, in deriving S-STRUCTURE from D-STRUCTURE.
derived score n
(in statistics) any type of score other than a RAW SCORE. A derived score is
calculated by converting a raw score or scores into units of another scale.
For example, the number of correct responses in a text (the raw score)
may be converted into grades from A to F (a derived score).
see also STANDARD SCORE
description n
see ESSAY
descriptive adequacy n
see GENERATIVE THEORY
descriptive writing n
see MODES OF WRITING
descriptive function n
see FUNCTIONS OF LANGUAGE 1
descriptive grammar
descriptive grammar n
a grammar which describes how a language is actually spoken and/or
written, and does not state or prescribe how it ought to be spoken or
written.
If a descriptive grammar of a non-prestige variety of English were written,
it might show, for example, that speakers of this variety sometimes
said:
I seen ’im. instead of I saw him.
’im ’n’ me done it. instead of He and I did it.
see also PRESCRIPTIVE GRAMMAR
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