Developing Lexical Competence in Non-Linguistic Specializations: A Critical Review of Literature and Emerging Research Directions

Abstract

This article examines the concept of lexical competence and provides a comprehensive review of scholarly literature addressing its development within the context of English for Specific Purposes (ESP). Despite its long-standing history in applied linguistics, lexical competence still lacks a single, unified definition. In ESP instruction, developing lexical competence requires learners to acquire not only subject-specific terminology and conceptual vocabulary but also high-frequency general academic words, semi-technical items, and relevant phraseological units. The analysis reveals that effective lexical competence development cannot be limited to the teaching of terminology in isolation; rather, it must integrate general, academic, semi-technical, and professional vocabulary within a coherent instructional framework. A review of methodological trends demonstrates that although different approaches have been employed across historical periods, content-and-language integrated approaches—such as CLIL and ICLHE—are considered particularly effective for teaching disciplines characterised by academic and conceptual language, including mathematics. These approaches promote deeper lexical processing, contextual usage, and meaningful engagement with subject-specific discourse.