a distinct part of anything arranged in divisions; a division of a complex whole or organized system.
2.
one of the principal branches of a governmental organization: the sanitation department.
3.
( initial capital letter ) one of the principal divisions of the U.S. federal government, headed by a Secretary who is a member of the President's cabinet.
4.
a division of a business enterprise dealing with a particular area of activity: the personnel department.
5.
a section of a retail store selling a particular class or kind of goods: the sportswear department.
6.
one of the sections of a school or college dealing with a particular field of knowledge: the English department.
7.
one of the large districts into which certain countries, as France, are divided for administrative purposes.
8.
a division of official business, duties, or functions: judicial departments.
9.
a sphere or province of activity, knowledge, or responsibility: Paying the bills is not my department.
10.
( usually initial capital letter ) U.S. Army.(formerly) a large geographical division of the U.S. or its possessions as divided for military and defense purposes: the Hawaiian Department.
Origin: 1730–35; < Frenchdépartement, equivalent to départ(ir) (see depart) + -ment-ment
mid-15c., "a going away, act of leaving," from O.Fr. département (12c.), from L.L. departire (see depart). French department meant "group of people" (as well as "departure"), from which English borrowed the sense of "separate division, separate business assigned to
someone in a larger organization" (c.1735). Meaning "separate division of a government" is from 1769. As an administrative district in France, from 1792.