Rotundus

Rotundus is a Latin adjective meaning round or circular. In scientific naming, it is commonly used as a species epithet to describe a rounded morphology of an organism or its parts. Because Latin was historically the language of taxonomy, many species across plants, animals, and fungi bear the epithet rotundus or its gendered variants (e.g., rotunda, rotundum).

One widely cited example is Cyperus rotundus, the purple nutsedge, a perennial sedge that has become a troublesome weed in many tropical and temperate regions. The name refers to the rounded likeness of its tubers. Other uses of rotundus exist in various taxa, often indicating rounded leaves, fruits, or other features.

In anatomy and medicine, rotundus appears in neutral or neuter noun phrases such as foramen rotundum, the round opening in the sphenoid bone through which the maxillary nerve passes. The term illustrates how Latin descriptors are applied to shapes in anatomical context.

As a descriptive epithet, rotundus does not identify a single taxon; instead it signals morphology and can be found in many unrelated groups. Its usage is primarily historical and descriptive, reflecting a characteristic feature rather than a distinct lineage.