Vocabulary glosses are considered effective learning tools since they decrease incorrect meaning inferences from context while keeping reading uninterrupted. The purpose of the present study was to examine the impact of different gloss conditions on intermediate EFL learners' vocabulary retention and production. The participants were 101 EFL learners selected based on their performance on PET and randomly assigned to one control and two experimental groups. In the single gloss experimental group vocabulary was taught using glossed texts with one definition for each gloss while the multiple gloss experimental group received the same texts with three definitions for each gloss. The participants in the control group received the texts without any glosses but were encouraged to consult their dictionaries instead. All the participants took part in vocabulary retention and production posttests after the treatment and those in the two experimental groups answered a questionnaire about their attitudes towards using glosses. The results of the one-way ANOVA confirmed that the two gloss conditions contributed to vocabulary retention and production. Moreover, the results indicated that single gloss group did significantly better on vocabulary retention test. However, no significant difference was found between the single and multiple gloss groups on the vocabulary production test.