flank

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun The section of flesh on the body of a person or an animal between the last rib and the hip; the side.
• noun A cut of meat from the flank of an animal.
• noun A lateral part or side.
• noun The right or left side of a military formation.
• noun The right or left side of a bastion.
• transitive verb To protect or guard the flank of.
• transitive verb To menace or attack the flank of.
• transitive verb To be placed or situated at the flank or side of.
• transitive verb To put (something) on each side of.

from The Century Dictionary.

• noun A spark or flake of fire.
• To stand or be placed or posted at the flank or side of; border at the side or sides: as, the flanking troops of an army.
• Specifically Milit.: To attack or threaten the side or flank of; place troops so as to command, threaten, or attack the flank of.
• To pass round or turn the flank of; march or move along or past one side of, as an opposing army.
• To secure or guard the flank of: as, they flanked their position with abattis.
• To occupy a flank position; border; touch: with on.
• noun The posterior part of either side of an animal, between the ribs and the hip; also, the thin piece of flesh constituting this part.
• noun In entomology, the pleura or side of an insect's thorax.
• noun Milit., one of the sides of an army, or of any of its divisions, as a brigade, regiment, or battalion: as, to attack the enemy on the right flank.
• noun Hence A side of anything: as, the flanks of a building.
• noun In fortification, that part of a bastion which reaches from the curtain to the face, or any part of a work that defends another work by a fire along the outside of its parapet. See cut under bastion.
• noun The acting surface of a cog inside the pitch-line.
• noun plural In farriery, a wrench or any other injury to the back of a horse.
• noun In leather manufacturing, the part of a hide from the side of a beast.
• Pertaining to a flank or side.

from the GNU version of the Collaborative International Dictionary of English.

• intransitive verb To border; to touch.
• intransitive verb To be posted on the side.
• transitive verb To stand at the flank or side of; to border upon.
• transitive verb To overlook or command the flank of; to secure or guard the flank of; to pass around or turn the flank of; to attack, or threaten to attack; the flank of.
• noun The fleshy or muscular part of the side of an animal, between the ribs and the hip. See Illust. of beef.
• noun The side of an army, or of any division of an army, as of a brigade, regiment, or battalion; the extreme right or left.
• noun (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.
• noun (Arch.) The side of any building.
• noun That part of the acting surface of a gear wheel tooth that lies within the pitch line.
• noun (Mil.) an attack upon the side of an army or body of troops, distinguished from one upon its front or rear.
• noun (Mil.) a certain number of troops drawn up on the right or left of a battalion; usually grenadiers, light infantry, or riflemen.
• noun (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.
• noun (Mil.) any part of the right or left wing formed at a projecting angle with the line.
• noun the first men on the right, and the last on the left, of a company, battalion, etc.
• noun a march made parallel or obliquely to an enemy's position, in order to turn it or to attack him on the flank.
• noun 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.
• noun salient points in a national boundary, strengthened to protect the frontier against hostile incursion.
• noun 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.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• adjective nautical Maximum (of speed). 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 (All ahead flank!).
• noun anatomy The flesh between the last rib and the hip; the side.
• noun cooking A cut of meat from the flank of an animal.
• noun military The extreme left or right edge of a military formation, army etc.
• noun The side of something, in general senses.
• noun The outermost strip of a road.