Unlike earlier studies that approach academic vocabulary learning cognitively, this case study situates vocabulary learning in the classroom context. It features the teaching and learning of academic writing in an EMI program in a Thai university, focusing on five EFL students' use of academic, technical, and translingual lexicons to construct their textual identities in their literacy autobiographies (LAs). Data were collected from a semester-long and autoethnographic-researchoriented academic writing course that focused on a multi-draft LA writing project. They included teaching documents, field notes, students' LAs, weekly reading journals, and course reflections. These data were examined both quantitatively, i.e., by using AntWordProfiler, and qualitatively, i.e., by adopting a classroom-writing-ecology-and-translanguaging perspective. Both the core Academic Word List (AWL)-570 and a word list specifically for social sciences were referenced. All students were found to have grown in their understanding and use of the academic vocabulary and other resources in their later LA drafts and that they used these resources in an orchestrated manner. This study challenges ESP and EAP professionals to adopt a more holistic and dynamic view of their students' meaning-making repertoires in academic writing.