This study examines the integration of digital thesaurus tools into academic writing instruction as a means ofenhancing students’ lexical competence. Academic writing requires precise terminology, an advanced vocabulary range,and a nuanced understanding of semantic relationships–areas in which many students experience persistent difficulties.The research proposes a structured pedagogical framework for systematic thesaurus integration and evaluates its effectivenessthrough implementation with 73 students across three disciplinary contexts. The results demonstrate statisticallysignificant improvements in lexical diversity, terminological accuracy, and overall writing quality. The proposed frameworkemphasizes explicit instruction, guided practice, authentic application, and reflective analysis. The findings indicate thatappropriately scaffolded thesaurus use enhances, rather than diminishes, students’ critical engagement with languageand supports the development of advanced academic writing skills.