and : mythonyms that prevail in , , and .

Julius Caesar Arantius first described the hippocampus and proposed the term . Years later, French anatomists called the structure ram's horns, and a decade later, it was named cornu ammonis. Although both concepts were first associated with the same structure, their use has expanded to include different but related structures. This situation can make understanding and applying the terminology more difficult. The objective of this work was to determine the presence of the terms , and their variants in , , and , evaluating their congruence in said terminologies, in addition to examining the etymology of both terms. We searched , , and for terms containing the concepts , , and their derivatives. We analyzed the terms and from their etymology by examining several Latin texts. This analysis included the dissection of the hippocampus and fornix and a review of the RAT rules. The etymological analysis indicated that the refers to a sea horse; however, the term also has a mythological background. , on the other hand, refers to the horns of an Egyptian god. The terminologies present discrepancies regarding the terms derived from and . Although both terms appear in various terminologies, they are mythonyms that fail to describe the structure they refer to or meet the requirements set by FIPAT.