An urn is a vase, often with a cover, with a typically narrowed neck above a rounded body and a footed pedestal. Describing a vessel as an "urn", as opposed to a vase or other terms, generally reflects its use rather than any particular shape or origin. The term is especially often used for funerary urns, vessels used in burials, either to hold the cremated ashes or as grave goods, but is used in many other contexts.

Large sculpted vases are often called urns, whether placed outdoors, in gardens or as architectural ornaments on buildings, or kept inside. In catering, large vessels for serving tea or coffee are often called "tea-urns", even when they are metal cylinders of purely functional design.

Urns are also a common reference in thought experiments in probability wherein marbles or balls of different colors are used to represent different results and the urn represents the "container" of the whole set of possible states.