Department \De*part"ment\, n. [F. d['e]partement, fr. d['e]partir. See Depart, v. i.]

1. Act of departing; departure. [Obs.]

Sudden departments from one extreme to another. --Wotton.

2. A part, portion, or subdivision.

3. A distinct course of life, action, study, or the like; appointed sphere or walk; province.

Superior to Pope in Pope's own peculiar department of literature. --Macaulay.

4. Subdivision of business or official duty; especially, one of the principal divisions of executive government; as, the treasury department; the war department; also, in a university, one of the divisions of instruction; as, the medical department; the department of physics.

5. A territorial division; a district; esp., in France, one of the districts composed of several arrondissements into which the country is divided for governmental purposes; as, the Department of the Loire.

6. A military subdivision of a country; as, the Department of the Potomac.

Source: Webster's Revised Unabridged Dictionary (1913)