This study aimed to explore the effect of multimedia glosses on the vocabulary acquisition of Iranian intermediate EFL learners. The program employed in this study provided the learners with glosses for words in the form of sounds and videos. The participants were 40 intermediate EFL learners studying English at a private institute in Esfahan. The participants were assigned to experimental and control groups. Participants were given the exact reading context from a software called "Tell Me More." The experimental group had access to multimedia glosses for unknown words. The learners were granted access to the glosses by clicking on the highlighted words. The control group, regarding the clarification of the unknown word lexis, received help from the researcher through the conventional method and had access to a dictionary. After 10 sessions, a vocabulary test was given to experimental and control groups. The application of an independent t-test indicated that the performance of the participants exposed to multimedia glosses was significantly superior to that of the control group. The present study offers valuable insights for CALL material designers in selecting the optimal combination of modalities to facilitate L2 vocabulary acquisition.
