pinnatum

Pinnatum is a Latin adjective used as a specific epithet in scientific names to indicate a feather-like or pinnate morphology. It derives from pinnatus, meaning feathered or winged, and is used across taxonomic groups to describe a feature that resembles a feather or consists of leaflets arranged along a central axis.

In plants, pinnatum commonly refers to structures with pinnate organization, such as pinnate leaves with paired leaflets along a rachis or pinnate inflorescences where lobes branch in a feather-like pattern. The term may appear in descriptions of a species’ leaves, stems, or inflorescence architecture.

In animals, pinnatum may describe feather-like appendages such as pinnate or bipectinate antennae, lobed fins, or other feathered features that resemble a feather. The precise morphology varies by taxon but the common theme is a feathered, divided, or wing-like form.

Pinnatum is an epithet, not a taxon by itself, and as with other Latin epithets it agrees in gender with the genus name (pinnatus, pinnata, or pinnatum). Its usage is descriptive rather than systematic, serving to highlight a notable morphological trait.

See also pinnatus, pinnata.