villosum

Villosum is a Latin adjective used as a species epithet in botanical nomenclature. In Latin, villosus (masc.), villosa (fem.), and villosum (neuter) all derive from villus, meaning a threadlike or hairlike filament; the neuter form villosum is used to agree with neuter genus names. As an epithet, villosum signals a plant with noticeable hairiness on leaves, stems, or other surfaces.

Because it is an epithet rather than a taxon, villosum appears in many different genera across flowering plants. The use is descriptive rather than genealogical, often marking pubescence that can aid in identification or taxonomy. The term is commonly found in keys and descriptions that distinguish hairy forms from glabrous or less-hairy relatives.

Solanum villosum, commonly known as hairy nightshade, is a member of the nightshade family (Solanaceae). It is described as having hairy shoots and leaves and small berries that mature to yellow or orange. The plant is often considered a weed and some populations may be toxic if berries are consumed.

In botanical usage, villosum remains a descriptive epithet used in many genera, illustrating how morphology is reflected in scientific naming.