Patrol

v. i.	1.	To go the rounds along a chain of sentinels; to traverse a police district or beat. [imp. & p. p. Patrolled ; p. pr. & vb. n. Patrolling.]
v. t.	1.	To go the rounds of, as a sentry, guard, or policeman; as, to patrol a frontier; to patrol a beat.
n.	1.	(Mil.) A going of the rounds along the chain of sentinels and between the posts, by a guard, usually consisting of three or four men, to insure greater security from attacks on the outposts.
	2.	Any perambulation of a particular line or district to guard it; also, the men thus guarding; as, a customs patrol; a fire patrol. In France there is an army of patrols to secure her fiscal regulations. - A. Hamilton.
	3.	See Boy Scout.

Noun	1.	patrol - a detachment used for security or reconnaissance
	2.	patrol - the activity of going around or through an area at regular intervals for security purposes
	3.	patrol - a group that goes through a region at regular intervals for the purpose of security
Verb	1.	patrol - maintain the security of by carrying out a control Synonyms: police

Argus, Charley, airplane spotter, beat, course, cover, defend, defending, do, fire patrolman, fire warden, fireguard, forward observer, go over, guard, guarding, keep guard, keep vigil, keep watch, lookout, lookout man, measure, mount guard, night watchman, overpass, pass over, pass through, patroller, patrolman, perambulate, peregrinate, pererrate, picket, ply, police, protect, protecting, protection, range, range over, reconnoiter, rounds, roundsman, safeguarding, scour, scour the country, scout, sentinel, sentry, spotter, stand guard, stand sentinel, sweep, track, transit, travel over, travel through, traverse, vedette, vigilance, voyage, watch over, watcher, watchfulness, watchkeeper, watchman