(born 1928), US theoretical linguist; full name Avram Noam Chomsky. Noted for expounding the theory of generative grammar, he also theorized that linguistic behaviour is innate, not learned, and that all languages share the same underlying grammatical base. Chomsky is known also for his opposition to American involvement in the Vietnam War and the Gulf War. Notable works: Syntactic Structures (1957) and Aspects of the Theory of Syntax (1965).