Flank

[Julene]

The side of a persons or animals body between the ribs and the hip.

[Monty]

The extreme left or right of a military formation. The following is an extract:
[Flank] attack ([Mil].), an attack upon the side of an army or body of troops, distinguished from one upon its front or rear.
Flank company (Mil.), a certain number of troops drawn up on the right or left of a battalion; usually grenadiers, light infantry, or [riflemen].
Flank defense (Fort.), protection of a work against undue exposure to an [enemys] direct fire, by means of the fire from other works, sweeping the ground in its front.
Flank en [potence] (Mil.), any part of the right or left wing formed at a projecting angle with the line.
Flank files, the first men on the right, and the last on the left, of a company, battalion, etc.
Flank march, a march made parallel or obliquely to an enemys position, in order to turn it or to attack him on the [flank].
Flank movement, a change of march by an army, or portion of one, in order to turn one or both wings of the enemy, or to take up a new position.
[Flanks] of a [frontier], [salient] points in a national boundary, strengthened to protect the frontier against hostile incursion.
Flank patrol, detachments acting independently of the column of an army, but patrolling along its [flanks], to secure it against surprise and to observe the movements of the enemy.