Duabus

Duabus is the feminine dative and ablative plural form of the Latin numeral duo, meaning “to two” or “by two” when modifying a feminine noun. In Latin, cardinal numerals decline to agree with the gender, number, and case of the nouns they modify, so duabus is used with feminine nouns in the dative or ablative plural.

In the broader paradigm for duo, the feminine forms include duae (nominative plural), duas (accusative plural), and duarum (genitive plural). The masculine and neuter dative/ablative plural form is duobus. The feminine dative/ablative plural duabus therefore functions as the instrument or indirect-object form when the noun is feminine.

Usage examples include duabus manibus (with two hands) and duabus partibus (in two parts). The form also appears in Classical and Late Latin texts where the numeral is explicitly declined to agree with a feminine noun in dative or ablative plural.

Overview: duabus is a grammatical form rather than a standalone lexical item. It illustrates how Latin numerals govern agreement with noun gender and case, and it is encountered primarily in scholarly linguistic references, grammars, and inscriptions or texts that preserve explicit numeral agreement. In modern contexts, its usage is confined to Latin studies and historical literature.