Prototype theory makes a crucial distinction between central and peripheral sense of words. Geeraerts explores the implications of this model for a theory of semantic change, in the first full-scale treatment of the impact of the most recent developments in lexicological theory on the study of meaning change. He identifies structural features of the development of word meanings which follow from a prototype-theoretical model of semantic structure, and incorporates these diachronic prototypicality effects into a theory of meaning change.
Dirk Geeraerts holds the chair of theoretical linguistics at the University of Leuven, Belgium. He is the founder of the research unit Quantitative Lexicology and Variational Linguistics (QLVL). His main research interests involve the overlapping fields of lexical semantics, lexicology, and lexicography, with a theoretical focus on cognitive semantics.
His involvement with cognitive linguistics dates from the 1980s, when in his PhD thesis he was one of the first in Europe to explore the possibilities of a prototype-theoretical model of categorization. As the founder of the journal Cognitive Linguistics and as the editor (with Hubert Cuyckens) of the Handbook of Cognitive Linguistics, he played an instrumental role in the international expansion of cognitive linguistics.
Geeraerts is one of the outspoken advocates of the implementation of empirical methodologies, such as corpus linguistics in cognitive linguistic research and also argues for the involvement of more pragmatic elements such as contextual factors that influence the construal of word meanings and the choice of 'names' for concepts and the historical implications these have in relation to etymology and lexicology.