Abstract-The present research study investigated potential impacts of the etymological elaboration and rote memorization on the learning of the English idioms by Iranian EFL learners. Sixty (N = 60) female students of the Iranmehr language school were selected among a total number of 100 based on their performance on a Nelson proficiency test, and were assigned into two groups. Prior to the study an idiom achievement test was administered to the learners in both groups to make sure that they did not know the idioms at the outset. Subsequently, the participants in the experimental group received the idioms with the relevant etymological elaborations, while those in the control group were asked to memorize the same idioms without the etymological elaborations for15 sessions. An independent samples t-test was used to compare the mean scores of both groups on the posttest. The results revealed that elaboration of idioms was significantly more effective than learning the same idioms by rote memorization.