A thesaurus is essential for language development and information retrieval. It is crucial in indexing, search optimization, and linguistic research. Maithili, a constitutionally recognized Indian language, lacks a standardized digital thesaurus.Morever, Maithili words are currently preserved only in printed dictionaries, with no existing digital word database. This lack of structured linguistic resources limits research, NLP advancements, and the language’s integration into emerging web technologies.This study addresses the issue by designing and developing the Online Maithili Language Thesaurus (OMLT) to bridge the technological and linguistic divide. OMLT is a significant step toward digitizing Maithili, enhancing its usability in modern technologies and promoting its presence in the global linguistic environment.