With the: an open space constituting the scene of a battle or contest; the field of battle. Also figurative. Now archaic and rare.

In various phrases. (For declare, levy, wage war, see the verbs.) to go to waror †wars: to enter on hostilities. to go to the war(s) (archaic): to go…

to take the field: to commence military operations, to begin a campaign; to enter active (military) service; to go on to a sports field at the…

to go (forth) a warfare, to go to the war; also to go (etc.) on warfare, to pass (forth) in warfare (Scottish); to send a warfare. Also a warfare…

to go (forth) a warfare, to go to the war; also to go (etc.) on warfare, to pass (forth) in warfare (Scottish); to send a warfare. Also a warfare…

Originally and chiefly Scottish. intransitive. To fight. Obsolete.

intransitive. To go out for a specified or implied purpose. To march as a soldier; to leave one's home or country for a war or battlefield; (later…

In various phrases. (For declare, levy, wage war, see the verbs.) to go to waror †wars: to enter on hostilities. to go to the war(s) (archaic): to go…

Among North American Indians: The path or route taken by a warlike expedition. to be(also go) on the warpath: to go to war, seek the foe, be out…

to wash one's spears (sc. in blood): a phrase attributed to South African chiefs as expressing their motive for going to war.