Abranchiate is an unusual word that refers to animals that lack gills or any other respiratory structures that are typically found in aquatic animals. Some synonyms for abranchiate include apneustic, meaning without lungs, and agillate, referring to animals that lack gills. Another synonym is pharyngeal breather, which describes animals that breathe through openings in their pharynx, rather than through gills or lungs. Other related terms include pulmonary breather, used to describe animals that breathe through lungs, as well as cutaneous breathers, which are animals that breathe through their skin. All of these terms can be useful in different contexts, depending on the species being described and the specific respiratory structures involved.