Science mapping the literature in Applied Linguistics secondary research: navigating knowledge evolution from an epistemic perspective (1970–2022)

Applied Linguistics (AL) research has undergone significant transformation in recent decades, accompanied by a surge in secondary research within the field. Using WoS data, we conducted an extensive bibliometric analysis of 881 secondary research articles and 44,752 references spanning 1970 to 2022. Utilizing CiteSpace's “author co-citation network,” “keyword co-occurrence network,” and “burst detection” analyses, we identified core research clusters, their key topics, connections, and significant bursts. Then we synthesize all the main clusters' content through in-depth analysis. Our findings reveal the growing popularity of secondary research in AL, with substantial contributions from Asian countries despite Anglo-American dominance. Key disciplines influencing the AL's intellectual structure include Psychology, Neurology, Sociology, Education, and Computer Science. Four thematic strands anchor AL's conceptual structure: Language Education & Computer Science, Psycholinguistics, Neurolinguistics, and Sociolinguistics. The top-ranked co-cited authors by burst strength are Moher, Chomsky, and Botting. Using a data-driven theory of scientific revolution, we identify emerging research trends and track dynamic changes from an epistemic perspective. This dynamic perspective contributes to a more nuanced understanding of the evolution of the AL domain, signaling a new era of Critical Applied Linguistics. This study, an empirically-based overview of AL secondary research, offers important implications for future research.