Superorder Ratitae is a group of flightless birds that includes ostriches, emus, rheas, kiwis, and cassowaries. This group is characterized by a flat breastbone without a keel, which makes them unable to fly. There are several synonyms for Superorder Ratitae, including "Paleognathae," which means "ancient jaw" and refers to the primitive structure of the bird's jaw. Another synonym is "ostrich-like birds," which is a more straightforward description of the group's physical appearance. Additionally, the term "ratites" is often used to refer to Superorder Ratitae, which comes from the Latin word "ratitus" meaning "without a raft." Overall, there are many different ways to refer to Superorder Ratitae, each with its own unique connotations and meanings.