Available Definitions:
1) n. - An open field; a large, open plain without considerable hills. SeeChampaign.
2) n. - A connected series of military operations forming a distinct stage in a war; the time during which an army keeps the field.
3) n. - Political operations preceding an election; a canvass.
4) n. - The period during which a blast furnace is continuously in operation.
5) v. i. - To serve in a campaign.