squama

Squama, plural squamae, is a Latin term meaning scale or plate. In biology and anatomy it describes flat, scale-like structures or surfaces. The word is used chiefly in compound anatomical terms and histology, rather than as a standalone taxon.

In anatomy, squama refers to a flat, plate-like part of a bone or skull. Notable examples include the squama temporalis, the flat, scale-like part of the temporal bone that forms part of the skull’s side, and the squama frontalis, the forehead portion of the frontal bone. These designations emphasize the plate-like geometry of these regions.

In histology, the term underlies the name squamous epithelium, describing flat, scale-like cells. Stratified squamous epithelium consists of several layers of such cells and lines areas subject to abrasion, such as the skin, mouth, and esophagus. The adjective squamous derives from squama and is used in many related terms, including squamous cell carcinoma and squamous metaplasia.

Beyond these uses, squama serves as a descriptive root in anatomical nomenclature to denote flat plates or scales on various organs or structures. It is not a modern taxonomic name in itself but a historical Latin term that remains common in descriptive anatomy and histology.