Nullaffixbildung

Nullaffixbildung is a term in morphology describing the formation or realization of grammatical forms without an overt affix, by means of a zero morpheme. In many languages, affixes such as suffixes or prefixes encode grammatical information (number, case, tense). A zero affix is an abstract morpheme with no phonological manifestation, yet it contributes to the form of the word in the paradigm. Null affixation therefore refers to cases where the base form remains unchanged or where a form lacks an audible affix while still bearing grammatical meaning.

In practice, zero morphemes occur in inflectional systems when two or more paradigm cells share the same phonological form, or when the expected affix is absent. These zero forms can be productive in plural marking, case marking, or verb conjugation, and they must be distinguished from irregular forms obtained by suppletion or ablaut. For example, in English some nouns have a zero plural, as in fish and deer, where the plural form is not marked by a distinct suffix. Zero forms also appear in contexts where the form is shared across singular and plural, or where tense or mood is indicated without an audible affix. Derivational cases exist as well, though they are sometimes described as zero-derivation rather than zero affix formation.

The concept helps formalize analyses of inflection and supports computational morphology that must account for forms with no overt affix. Debates exist about whether zero morphemes are true morphemes or analytical conveniences, but most frameworks treat them as legitimate components of a language’s affix inventory.