Deirdre Susan Moir Wilson, FBA is a British linguist and cognitive scientist. She is emeritus professor of Linguistics at University College London and research professor at the Centre for the Study of Mind in Nature at the University of Oslo. Her most influential work has been in linguistic pragmatics—specifically in the development of Relevance Theory with French anthropologist Dan Sperber. This work has been especially influential in the Philosophy of Language. Important influences on Wilson are Noam Chomsky, Jerry Fodor, and Paul Grice. Linguists and philosophers of language who have been students of Wilson include Stephen Neale, Robyn Carston and Tim Wharton.

Relevance theory is a framework for understanding the interpretation of utterances. It was first proposed by Dan Sperber and Deirdre Wilson, and is used within cognitive linguistics and pragmatics. The theory was originally inspired by the work of Paul Grice and developed out of his ideas, but has since become a pragmatic framework in its own right. The seminal book, Relevance, was first published in 1986 and revised in 1995.