caeli

Caeli is the genitive singular form of caelum, a Latin noun meaning the sky or heaven. In Classical and Ecclesiastical Latin, caeli most often functions as a possessive, translating as “of the sky” or “of heaven.” The base noun caelum is neuter and belongs to the second declension; its full paradigm includes caelum (nom. sing. and acc. sing.), caeli (gen. sing.), caelo (dat. and abl. sing.), and caela (nom. and acc. pl.). The plural genitive is caelorum, and the plural dative/ablative is caelis.

Caeli appears in a number of standard Latin phrases. A well-known example is caeli et terrae, meaning “the heavens and the earth.” It can also occur in constructions such as ex caelo, “from the sky/heaven.” The related adjective caelestis means “heavenly” or “celestial,” formed from the same root and common in religious, literary, and scientific Latin.

Usage and context: today, caeli is primarily encountered in linguistic study, textual criticism, or discussions of Latin poetry, theology, and liturgy. It is not a modern term with independent usage outside of Latin grammar and set expressions; rather, it functions within phrases that refer to the heavens, the divine realm, or celestial phenomena. Its importance lies in illustrating how Latin expresses possession and relation to the sky or heaven, and in how related forms such as caelum and caelestis organize a family of terms around celestial ideas.