(crystallography) The smallest repeating structure (parallelepiped) of atoms within a crystal, from which the structure of the complete crystal can be inferred.

plural of unit cost

The cost to acquire a unit of a good or service for a specific quantity that is purchased.

(historical) The Thirteen Colonies that became the United States of America.

(archaeology) A pit, trench, shovel test hole, (etc.) or other result of scientific excavation.

plural of United Statesian

An Irish nationalist advocating a United Ireland.

A sovereign state that would cover the whole of the island of Ireland.

(astronomy) The (otherwise unnamed) unit of density of electromagnetic radiation from a radio star, equal to 10⁻²⁶ watts per square meter per hertz

plural of unit matrix