[Edit]

A government department in the United States, Australia and Switzerland corresponds to a ministry in other systems:

Department (US government)

Department (Australian government)

Department (Swiss government)

Department (subnational entity) - a geographical and administrative division within a country.

Part of an institution such as a commercial company (see departmentalization) or a non-profit organization such as a university.

Academic department

A department store is a retail store that includes many specialized departments such as clothing or household items.

In the US military:

"Department" is a term used by the U.S. Army, mostly prior to World War I.

A naval Department is a section devoted to one of several major tasks.

Part of a state or municipal government:

Fire department

Police department