Theoreticians have been asking for a long time what processes are involved in comprehension of figurative language, but psycholinguists have only recently addressed this question. One specific type of figurative expression, the metaphor, has been the focus of much recent research, in part because it promises to contribute much to the understanding of language processing in general and figurative language comprehension specifically. Most theories of semantic processing have focused on literal expressions, and several of these theories explained language processing successfully until they were extended to figurative expressions. Unlike literal expressions which are either true or false, metaphors interpreted literally are either false or nonsensical, and meaningful only if a figurative interpretation has been constructed. Metaphors are unique because they can be both literally meaningless or false and figuratively meaningful at the same time. The amount of psycholinguistic and cognitive research compiled on the metaphor does not reflect its historical importance in the development of language and concepts. For centuries metaphors have provided playwrights, authors, poets, and educators with a vehicle for creating new concepts and images, providing language users with a flexibility not available in literal expressions. (Author/MSE)