ID10M-JAM: Stress-Testing Idiom Identification Under Challenging Context

Kai Golan Hashiloni, Lior Livyatan, Ofri Hefetz, Alon Mannor, Bar Cohen, Kfir Bar


Abstract
Large language models (LLMs) achieve strong performance on idiom identification benchmarks, yet their robustness to misleading contextual signals remains largely untested. We introduce ID10M-JAM, an adversarial extension of the ID10M dataset designed to jam model understanding by injecting coherent but conflicting context before each target sentence. For every sentence containing a potential idiomatic expression (PIE), we construct variants that deliberately invert contextual expectations: placing literal cues before idiomatic uses and idiomatic cues before literal ones. All variants are validated by human annotators to ensure naturalness and unambiguous interpretation for human readers. ID10M-JAM exposes systematic vulnerabilities in LLMs’ contextual reasoning, pushing idiom identification to its breaking point.
Anthology ID:
2026.findings-acl.1045
Volume:
Findings of the Association for Computational Linguistics: ACL 2026
Month:
July
Year:
2026
Address:
San Diego, California, United States
Editors:
Maria Liakata, Viviane P. Moreira, Jiajun Zhang, David Jurgens
Venue:
Findings
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Publisher:
Association for Computational Linguistics
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Pages:
20846–20864
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URL:
https://preview.aclanthology.org/ingestion-form-platform/2026.findings-acl.1045/
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Cite (ACL):
Kai Golan Hashiloni, Lior Livyatan, Ofri Hefetz, Alon Mannor, Bar Cohen, and Kfir Bar. 2026. ID10M-JAM: Stress-Testing Idiom Identification Under Challenging Context. In Findings of the Association for Computational Linguistics: ACL 2026, pages 20846–20864, San Diego, California, United States. Association for Computational Linguistics.
Cite (Informal):
ID10M-JAM: Stress-Testing Idiom Identification Under Challenging Context (Hashiloni et al., Findings 2026)
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https://preview.aclanthology.org/ingestion-form-platform/2026.findings-acl.1045.pdf
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