What is the meaning of Flank?

To attack the flank(s) of.

To defend the flank(s) of.

To place to the side(s) of.

To be placed to the side(s) of something (usually in terms of two objects, one on each side).

The lateral flesh between the last rib and the hip.

A cut of meat from the flank of an animal.

The extreme left or right edge of a military formation, army etc.

The sides of a bastion perpendicular to the wall from which the bastion projects.

The side of something, in general senses.

The outermost strip of a road.

The wing, one side of the pitch.

That part of the acting surface of a gear wheel tooth that lies within the pitch line.

Maximum. Historically faster than full speed (the most a vessel can sustain without excessive engine wear or risk of damage), now frequently used interchangeably. Typically used in an emergency or during an attack.

side, flank

a flank

flank

Source: wiktionary.org