[5] The meaning can overlap with that of sacrarium, a place where sacred objects (sacra) were stored or deposited for safekeeping.
Each curia had its own sacellum overseen by the celeres, originally the bodyguard of the king, who preserved a religious function in later times.
Claudius Pulcher, a censor at the time, had failed to maintain public access to a sacellum on his property.
In a manuscript from the Abbey of Saint Gall, sacellum is glossed as Old Irish nemed, Gaulish nemeton, originally a sacred grove or space defined for religious purposes, and later a building used for such.
[22] In Christian architecture, rooflessness ceases to be a defining characteristic and the word may be applied to a small chapel marked off by a screen from the main body of a church,[23] while an Italian sacello may alternatively be a small chapel or oratory which stands as a building in its own right.