de·part·ment 
(dĭ-pärtmənt)
(dĭ-pärtmənt)n.
1. A distinct, usually specialized division of a large organization, especially:
a. A principal administrative division of a government: the department of public works.
b. A division of a business specializing in a particular product or service: the personnel department.
c. A division of a school or college dealing with a particular field of knowledge: the physics department.
2. Department One of the principal executive divisions of the federal government of the United States, headed by a cabinet officer.
3. A section of a department store selling a particular line of merchandise: the home furnishings department.
4. An administrative district in France.
5. A unit of a warship's crew, organized by function, such as gunnery or engineering.
6. An area of particular knowledge or responsibility; a specialty: Getting the kids to bed is my department.
[French département, from Old French, separation, from departir, to divide; see DEPART.]
de′part·mental (dē′pärt-mĕntl) adj.
de′part·mental·ly adv.