The development and typology of number suppletion in adjectives

This paper looks at the cross-linguistically rare phenomenon of number suppletion in adjectives. I consider how such suppletion arises by looking at six known examples with a special focus on the Brittonic languages (Breton, Cornish and Welsh), which are discussed as an extended case study. Three generalisations are suggested on the basis of the typological study. First, adjectives denoting size ("small" and "big") are at the centre of this phenomenon. Second, where the etymology of the adjectives is known, the plural member of the suppletive pair for "small" develops from a lexeme denoting something having been divided into or consisting of small parts. These lexemes can also be used with some singular nouns and in such cases they denote the component structure of the referent. Finally, adjectives with number suppletion tend to mark plural number consistently in environments in which plural marking is otherwise optional or rare.