capacitas

Capacitas is a Latin noun meaning capacity, extent, or power to contain or hold, as well as figurative sense of ability or capability. The core sense is physical capacity—the amount of space a vessel or container can hold—and by extension the size or extent of any receptacle or area. In later and more general usage, capacitas also denotes mental, moral, or operational ability and potential.

Etymology and form: Capacitas derives from the adjective capax, meaning capable of containing, which itself comes from the root capere “to seize, grasp” with the suffix -ax. The abstract noun is formed with the suffix -tas. The word is feminine and belongs to the third declension in Latin.

Grammar: As a third-declension feminine noun, its principal forms are: nominative capacitas, genitive capacitatis, dative capacitati, accusative capacitatem, ablative capacitate; plural capacitates, capacitatum, capacitatibus, capacitates, capacitatibus.

Semantics and usage: In classical Latin, capacitas is used primarily for physical capacity—how much a container or space can hold. In Late Latin and medieval Latin, it broadened to refer more generally to capacity in sense of ability, power, or potential, including faculties of mind or capacity for action. Phrases in Latin literature and scholastic texts often employ capacitas alongside related terms such as capax, facultas, and potens to discuss suitability, capability, or capacity limits.

Descendants and related terms: Capacitas is the genealogical source of many Romance-language terms for capacity, such as capacidad (Spanish), capacité (French), capacità (Italian), capacidade (Portuguese), and capacity in English. The word remains of interest primarily in linguistic and historical contexts.

See also: capax, facultas, potentia, capacitas in philosophy.