The term "diapsids" is often used to describe a specific group of reptiles that share a common feature: two pairs of openings in their skull, behind their eyes. While "diapsids" is the most common term used to describe this group, there are a few other synonyms that can be used as well. For example, some sources may refer to diapsids as "two-holed reptiles," "two-orifice reptiles," or "double opening reptiles." These synonyms all refer to the same group of reptiles that includes lizards, snakes, and dinosaurs among others. Using different synonyms can help to add variety and clarity to discussions and descriptions of these fascinating creatures.