Gratissimum

Gratissimum is a neuter singular form of the Latin adjective gratissimus, meaning "most pleasing" or "most welcome." In biological nomenclature, gratissimum functions as a specific epithet in binomial names and must agree in gender with the genus name. The epithet conveys a qualitative assessment by the taxonomist who described the species, typically alluding to a desirable trait such as aroma, flavor, or appearance.

The epithet is common in botanical names, reflecting the importance of scent or taste in plant selection and use. One well-known example is Origanum gratissimum, the African oregano or wild marjoram, valued for its aromatic leaves and essential oils. The use of gratissimum is not restricted to any single taxonomic group; it appears in several other plant genera when the author wishes to highlight a favorable attribute.

In Latin, gratissimum derives from gratus or gratus, meaning pleasing or grateful, with the superlative suffix -issimus and neuter nominative/accusative ending -um. This form is chosen for neuter genera; masculine or feminine genera would employ gratissimus or gratissima, respectively.

See also binomial nomenclature; Latin in biology; epithet in taxonomy.