Rubrum

Rubrum is a Latin adjective meaning red. In classical Latin, rubrum is the neuter singular form of the comparative adjective ruber, rubra, rubrum, and it is used to describe red coloration when paired with a neuter noun. In modern scientific naming, rubrum often appears as a species epithet in botanical and zoological Latin, indicating red coloration of the organism or a part of it.

In taxonomy, rubrum is commonly used as an epithet across plants, animals, and fungi to highlight red characteristics, such as red leaves, flowers, or body parts. The most familiar example in botany is Acer rubrum, the red maple, a deciduous tree native to eastern North America. The use of rubrum in binomials follows historical conventions in botanical Latin, where the gender of the genus can influence the form of the epithet; rubrum is the neuter form, while other gendered forms such as rubrum, rubra, or ruber may appear in different contexts.

Beyond taxonomy, rubrum has a broader linguistic presence as part of color terminology in Latin texts and as a root in related words describing red in various languages. It is cognate with ruber and rubra and relates to terms that signify red in historical and scientific vocabulary, including the lineage of words that entered modern languages to describe the color red.