Derivational morphology
ID: derivational-morphology
Derivational morphology forms lexical items from existing bases, changing meaning and sometimes lexical category. It is part of linguistic morphology, alongside inflection, which supplies grammatical forms of a lexeme. The distribution of an affix matters as well as its visible spelling.[ref]
Essentials of Linguistics (2nd edition) by Catherine Anderson and others. §5.6, category selection and order of affixation
For example, adding
-ness to the adjective kind gives the noun kindness; adding un- to kind gives another adjective, unkind. Combining the operations yields unkindness. A category-sensitive analysis first forms unkind, then attaches -ness: this use of un- selects an adjective, whereas kindness is already a noun. The intermediate structure explains a restriction that merely listing the three morphemes misses. Derivational morphology therefore connects reusable word-building rules to both syntax and semantics. New to topics? Read the docs here!