from
The Collaborative International Dictionary of English v.0.48
Flank \Flank\ (fl[a^][ng]k), n. [F. flanc, prob. fr. L. flaccus
flabby, with n inserted. Cf. {Flaccid}, {Flanch}, {Flange}.]
1. The fleshy or muscular part of the side of an animal,
between the ribs and the hip. See Illust. of {Beef}.
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2. (Mil.)
(a) The side of an army, or of any division of an army, as
of a brigade, regiment, or battalion; the extreme
right or left; as, to attack an enemy in flank is to
attack him on the side.
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When to right and left the front
Divided, and to either flank retired. --Milton.
(b) (Fort.) That part of a bastion which reaches from the
curtain to the face, and defends the curtain, the
flank and face of the opposite bastion; any part of a
work defending another by a fire along the outside of
its parapet. See Illust. of {Bastion}.
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3. (Arch.) The side of any building. --Brands.
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4. That part of the acting surface of a gear wheel tooth that
lies within the pitch line.
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{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 enemy's 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
enemy's 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.
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