A research article (RA) title is the first and foremost feature that attracts the reader's attention, the feature from which she/he may decide whether the whole article is worth reading. The present study attempted to investigate syntactic structures and rhetorical functions of RA titles written in English and Persian and published in journals in three disciplines of Electrical Engineering, Psychiatry, and Linguistics. To this end, 750 English and 750 Persian RAs were randomly selected from reputable English and Persian journals in these fields and syntactic structures of their titles were analyzed based on Dietz’s (1995) taxonomy. The results revealed that, despite some similarities, there were some cross-linguistic and cross-disciplinary differences in title structures. The differences were found in title components and title length and style. Generally, English titles were shorter in length than Persian ones. Psychiatry titles were the longest, whereas Linguistics ones were the shortest. Although the majority of titles were single-unit ones, English authors used multiple-unit titles more than Persian ones. Multiple-unit titles were also employed the most in Linguistics RAs. No significant difference was found regarding combinations of multiple-unit titles in the two languages; however, topic-description combinations were the most frequent in Electrical Engineering and Linguistics titles, whereas topic-method ones were the most popular in Psychiatry titles. Moreover, the post-modified nominal group construction was the most frequent syntactic structure across single-unit titles. Such findings can contribute to the developments of English for Specific Purposes and provide some information about Persian and English RA titles structures in different disciplines.
