Suffixappliesbase

Suffixappliesbase is a term used in morphology and linguistic annotation to describe a property of certain suffixes: they attach to the underlying base form of a word (its lemma or stem) rather than to a surface inflected form. In theoretical and computational frameworks that distinguish base forms from inflected variants, suffixappliesbase indicates that the suffix’s productive scope is defined with respect to the base rather than the fully inflected word. This distinction can simplify description of regular derivational patterns and aid automatic parsing, lemmatization, and morphological generation.

In practice, suffixappliesbase can explain why a suffix behaves consistently across inflected contexts. For example, the English agentive suffix -er can attach to the verb base teach to yield teacher, regardless of the verb’s current tense or aspect in a sentence. Similarly, the nominalizing suffix -ness attaches to the base adjective happy to form happiness, rather than to some inflected form of happy.

Some analyses treat suffixappliesbase as a constraint in rule-based morphologies or as a criterion in finite-state models to determine affixation scope. Critics note that not all suffixes obey a base-only attachment, and in many languages affixation interacts with phonology and stem alternations in surface forms.

See also: lemma, stem, derivational morphology, inflection, affix, morpheme.