The lexical nature of idioms

• Idioms have distinctive lexical profile; constituent lexemes of idioms concurrently have:
• 1. Grammatical attributes of non-idiomatic nouns, 2. Discourse attributes distinguishing them from non-idiomatic nouns.
• A model of idiomaticity based on polysemy of constituent lexemes is developed.
• Idioms can be understood without recourse to conceptual metaphor.

In recent work, idioms have in many traditions been assimilated to the study of metaphor. An idiom such as ‘spill the beans’ is understood against the conceptual metaphors, THE MIND IS A CONTAINER and IDEAS ARE ENTITIES for instance. Such a treatment implies that idioms are processed online, calling up in their production the conceptual metaphors which support them. In this article an alternative treatment is put forward whereby idioms are lexical in nature. The argument has two parts. First, the constituent collocates of idioms share a number of key grammatical properties with non-idiomatic lexemes. Even in their idiomatic usage they must in some sense be normal lexemes. Secondly, at the same time, idioms are shown to be distinctive in terms of their discourse properties, in particular the fact of idiomaticity restricting the referentiality of idiomatic nouns. Drawing broadly on ideas developed within psycholinguistic treatments of idiomaticity, a model of idioms is developed whereby idioms are seen as lexically compositional against a rich polysemy of their stipulated, constituent lexemes. While, it may be inferred, metonymic and metaphoric associations led to the lexical polysemy of the constituent collocates, metonymy and metaphor play no necessary role in their online production and processing. The argument is developed on the basis of a detailed discussion of idioms in Nigerian Arabic. The data derives from a large, oral corpus (400,000 words), in which the conventional nature of idiomaticity is underscored by the quantitative preponderance of idiomatic meanings among basic body part nouns such as ṛaas ‘head’ and gaḷb ‘heart’.