irregularis

irregularis is a Latin adjective meaning irregular, uneven, or atypical. In scientific naming, irregularis often appears as an epithet in the binomial name of a species or subspecies to indicate an unusual trait relative to related taxa.

Etymology: irregularis derives from regularis ('regular') with the negative prefix in- assimilated before r, yielding irregularis. The epithet appears across plants, animals, and fungi.

Taxonomic usage: The epithet is descriptive rather than prescriptive about taxonomy. A species with this epithet may have irregular coloration, shape, pattern, or growth form relative to related species. The precise meaning is defined by the original description and comparison in the publication that established the name.

Beyond biology, irregularis can appear in other scientific or descriptive contexts to denote irregular or nonuniform features.

See also irregular, regularis.