The study of ethnic identity has received considerable attention in the field of psychology. However, the literature draws primarily from WEIRD populations and conflates race and ethnicity. Ethnic identity remains understudied in multi-ethnic and diverse contexts like India, where language is often used as a marker of ethnicity. This study conceptualised ethnicity on the basis of language and assessed the psychometric properties of the Multigroup Ethnic Identity Measure-Revised, in a multi-ethnic sample of young adults in Karnataka, India. The reliability, convergent validity (self-esteem, optimism, familial ethnic socialisation, national identity), concurrent validity (EIS-B) and factor structure of the measure were assessed. Additionally, differences in ethnic identity were examined between the majority and minority ethnic groups. The study provides support for the convergent and concurrent validity of the measure and confirms the correlated two-factor structure of exploration and commitment. Our results also showed that ethnic identity was more significant among majority group members, contradicting previous literature and highlighting the cultural significance of language as ethnicity. The study adds to the literature on the MEIM-R highlighting the applicability of this measure to multicultural settings with multiple definitions of ethnicity. © 2023, The Author(s) under exclusive licence to National Academy of Psychology (NAOP) India.