In linguistics, derivation is the process of creating new lexemes from other lexemes, for example by adding a derivational affix.
Derivational affixes usually apply to words of one syntactic category and change them into words of another syntactic category. For example, the English derivational suffix -ly changes adjectives into adverbs (slow > slowly).
Some examples of English derivational suffixes:
- A/N -ness (slow > slowness)
- A/V -ize (modern > modernize)
- N/A -al (recreation > recreational)
- N/V -fy (glory > glorify)
- V/A -able (drink > drinkable)
- V/N -ance (deliver > deliverance)
Note that derivational affixes are bound morphemes. In that, derivation differs from compounding, where free morphemes are combined. It also differs from inflection in that inflection does not change a word's syntactic category and does not create new lexemes, but new word forms.
For other processes of word formation, cf. conversion and compounding.