Mostafa Tajgozari - PhD student of TEFL, Department of English, Shiraz University, Shiraz, Iran. Ministry of Education, Fars Education Office, Iran
Katayoun Kalantari - MA student of TEFL, Department of English, Shiraz University, Shiraz, Iran

This study aimed to compare the effect of using glossaries in L1 (mother tongue) and L2 (target language) on vocabulary learning, recall, and retention of Iranian advanced EFL learners. To do so, a Standardized English Proficiency Test, Nelson proficiency test, was administered among 65 students from two institutes in Darab, Iran. 38 of whom were selected as the participants of this study. They were all males and were high school students who attend English classes in institutes three times a week with the age range of 14 to18. Then, they were divided into two comparison groups: L1 glossary and L2 glossary groups. Before the treatment a pretest of vocabulary was administered to both groups and after the treatment which lasted for 26 sessions of teaching 504 Absolutely Essential Words, Fifth Edition (Bromberg, Lieb, & Traiger, 2013), the same version of vocabulary test was given to both groups as posttest to check the effectiveness of the treatments. After collecting and analyzing the data, the results showed that both glossaries have positive effects on vocabulary learning, recall, and retention of Iranian advanced EFL learners while the L1 group outperformed the L2 group. The limitations and implications of this study, as well as its suggestions for future research, are also discussed

EFL learners, glossary, recall, retention, vocabulary