The word "Hemimastodontidae" refers to an extinct family of primitive proboscideans. While there are no direct synonyms for this term, it is often classified within the suborder of elephants, alongside other extinct and extant species like mammoths and mastodons. Other related terms might include "mastodonts" or "proboscideans," which refer to groups of animals that share similar anatomical features. However, due to the specific nature of the Hemimastodontidae family, it is not typically used in a broader sense to describe general categories of proboscideans. Nonetheless, for those studying paleontology or animal taxonomy, it is an important term to know.