Unlocking Academic Vocabulary: Corpus Insights from Open and Distance English Language Learning Coursebooks

Finding the right word that is neither too difficult nor too simple for English learners is one of the most serious problems in applied linguistics , given the undeniable association of vocabulary with comprehension, problems about which academic words need to be used in open and distance learning coursebooks for students' effective reading comprehension remain unsolved. This study serves this purpose by conducting data-driven research on the coursebooks of the National Open University of Nigeria. Therefore, this study uses Coxhead's (2000) Academic Word List (AWL) in a corpus of 6,802,300 words from first-year university coursebooks. The results indicate that while the AWL contains 9.47% of the lexical items in the corpus, certain items on the list frequently occur and exhibit distinct behaviours across disciplinary fields. Using frequency and range selection criteria, the study finds 181 AWL and 28 non-AWL word items used at least 1132 times in the NOUNC and at least 15 times across the 30 academic subjects. This study uncovers cross-disciplinary lexical features that can be used to develop vocabulary acquisition and help students participating in open and distance learning courses improve their academic reading and other language skills. In light of the above, the AWLNOUN could serve as a reference resource for educators and course designers in curriculum development for open and distance learning centres. Keywords: academic vocabulary; academic word list; AntWordProfiler; corpus analysis; English language coursebooks