Idiomatic expressions are linguistic expressions, grammatical forms, phrases or words that possess a figurative meaning which cannot be predicted from the individual components or literal meanings of the constituent parts (Fraser, 1970; Makkai 1972; Kovecses and Szabo, 1996). Idiomatic expressions play an important role in human communication, since their emotive and cultural connotations facilitate the expression of meaning at both linguistic and cultural level.

This article examines structural variation in idiomatic expressions in Arabic. A corpus of 440 idioms from the Saudi newspaper Al-Riyadh, which is published in Modern Standard Arabic, was analysed using a version of Moon’s (1998) framework of relative fixedness in English idiomatic expressions. This study descriptively categorises the types of variations of idiomatic expressions in this corpus in order to identify the key elements that convey the figurative meaning of these idioms. Analysis revealed, firstly, that structural changes in idiomatic expressions are possible and included, for example, lexical and grammatical variations such as transformation, addition, substitution and embedding. Secondly, the idiomatic expressions were shown to be subject to the rules of Arabic grammar but to have their own specific characteristics related to the correlation between their structural and semantic components. Such characteristics make idiomatic expressions less tolerant of grammatical changes than non-fixed expressions. Thirdly, the findings of the study confirmed the notion that all idioms contain a head word which helps to convey the meaning of the idiom.

Keywords: Text-linguistics, Idioms, Idiomatic expressions, Semantic, Syntax.