Improvement of phrase descriptions in English–Japanese dictionaries for learners – with a focus on idiom variants

The technological affordances of AI and online dictionaries have led to a shift away from paper-based dictionaries by Japanese English learners (JELs). However, paper-based English–Japanese dictionaries for learners (EJDLs) are still being published. In this connection, the aim of this paper is to improve phrase entries for a better description of EJDLS. Idiomatic phrases have not changed for a long time in EJDLs, as they tend to be morphologically and semantically invariant. However, idiom variants are observed. Using large-scale corpora, this paper presents examples of idiom variants and shows where and how idioms change, based on certain rules. This supplements previous findings in English linguistics. In addition, the results found in this study can be reflected in entries for idioms in the EJDLs, which have long remained unchanged.