This study aimed to investigate the students' knowledge and recognition of sense relations in two modes of learning: face-to-face learning and online learning, to examine the impact of sense relations in improving students' vocabulary knowledge. A total of eighty senior English language students, 40 from Isra University and 40 from the University of Jordan, were recruited to participate in this study, which followed a quantitative and descriptive method to design and answer the research questions: a) To what extent are senior English majors aware of sense relations at word-level and sentence-level? b) To what extent do senior English majors apply appropriate metalanguage in describing sense relations at the word-level, sentence-level, and collocations? c) Do students' grades in "semantics" correlate with their knowledge and recognition of sense relations? d) Which is more effective: face-to-face or online teaching of semantics at university level? Data was collected via a test containing three tasks that assessed students' knowledge of sense relations at the word-level, sentence-level, and collocation-level. The findings revealed that senior English language students struggle with sense relations at word-level, sentence-level, and collocation. Interestingly, the study indicated that the scores of the students exposed to face-to-face learning outperformed those exposed to online learning. Moreover, the study showed that the students at the University of Jordan slightly had better knowledge and recognition of sense relations than the students at Isra University. The findings of the study offer implications for educators and university instructors to integrate sense relations in the university's subjects to improve students' vocabulary knowledge. The study recommended conducting further studies in sense relations at different universities in Jordan. Keywords: sense relations, vocabulary knowledge, metalanguage, face-to-face learning, online learning