annua

Annua is the feminine form of the Latin adjective annuus, meaning yearly or annual. In Latin, adjectives change endings to agree with the gender of the noun they describe, so annua modifies feminine nouns, while annuus and annuum are the masculine and neuter forms, respectively. In English usage, annua appears mainly in scientific Latin phrases and taxonomic names, where it signals an annual habit or lifecycle.

In taxonomy and botany, the epithet annua or annuum is commonly used to indicate that a species completes its life cycle within one year. When applied to a genus with a feminine name, the form annua may appear; with a neuter genus, annuum is typical. Because botanical Latin preserves gendered endings, both forms convey the same general meaning but align with grammatical gender in the name.

Outside of scientific names, annua may appear in Latin-language texts or translations to describe yearly events, cycles, or characteristics. In modern English writing, annua is rare outside of scholarly, historical, or taxonomic contexts, where it helps indicate annual behavior or classifications derived from Latin terminology.

Related terms include annus, the Latin noun for year, and the English forms annual and perennial, which describe different plant lifecycles. Annua therefore functions as a linguistic marker rather than a standalone concept in most contemporary contexts, preserving its role primarily within Latin phrases and taxonomic nomenclature.