arcului

Arcului is a Romanian noun form that functions as the genitive and dative singular of arc. The word arc has several related senses, including an architectural curved structure spanning an opening and a portion of a circle in geometry. The form arcului appears whenever the noun arc is used in possessive or indirect-object contexts, for example lungimea arcului cercului, meaning the length of the circle’s arc.

Etymology and related forms: arc derives from Latin arcus, with Romanian developing arcului as the genitive/dative singular. The base nominative singular is arc; the plural nominative is arcuri, while the genitive/dative plural is arcurilor. The word is used across technical, architectural, and mathematical discourse, as well as in more general textual contexts.

Usage and examples: arcului is a grammatical form, not a standalone root meaning. It appears in phrases that express possession or indicate an indirect object to a noun, such as lungimea arcului cercului (the length of the circle’s arc) or părțile arcului (parts of the arch). In architectural descriptions, it may describe elements belonging to or belonging to an arch. In mathematical writing, it can appear in constructions that specify properties of an arc, its length, or its position relative to another curve or circle.

See also: arc, Romanian grammar, Romanian noun declensions. Arcului exemplifies how Romanian uses distinct genitive/dative forms to mark possession and indirect relation for masculine nouns ending in -arc, with arcului serving as the standard singular form.