Mental Representation of Multiple Default Plurals: Evidence from the Adaptation of English Loanwords in Arabic

The present work argues for the existence of multiple default regularities of plural formation in Arabic. As evidenced in the corpus of loanword adaptation in Jordanian Arabic, this study calls for a reassessment of the treatment of idiosyncratic plural forms in the mental lexicon. This investigation is in line with the dual mechanism theory where both memory and rule are active, but with more reliance on the default rule (feminine sound plural –aat) over memory (broken plural patterns). This avoidance of broken plural, which is less predictable and less transparent, is explained by a limited mental lexicon that defines such loanwords and thus blocks a successful mapping of the broken plural’s inflection in the memory. The failure of broken plural retrieval, especially with words that do not match the canonical root system (tri-consonantal), calls for the application of the default feminine sound plural, the most productive, transparent, and regular formation. As a result, frequency and memory association predicted by prosodic similarity between loanwords and the broken plural patterns do not contribute to avoiding the default -aat overgeneralization in the short term.