n. In ordinary language: The upper limb of the human body, extending from the shoulder to the hand, and including the latter.n. The same, exclusive of the hand; the upper limb from the shoulder to the wrist. It is divided into upper arm, or arm proper, from the shoulder to the elbow, and lower arm, or forearm, from the elbow to the wrist.n. In human anatomy, the anterior extremity from the shoulder-joint to the elbow-joint, represented by the extent of the humerus; the brachium, as distinguished from the forearm or antebrachium.n. In comparative anatomy and zoology: The fore limb of any vertebrate, especially when terminating in a prehensile extremity like a hand, more or less removed from the office of locomotion; the pectoral or thoracic limb; the diverging appendage of the scapular arch or shoulder-girdle; a fore leg, wing, pectoral fin, etc.n. Some diverging or radiating part or organ like or likened to an arm, as the arm of a cephalopod, the wing of a pteropod, the brachium of a brachiopod, and the ray of a starfish, sand-star, or crinoid.n. Anything formed on the type of the arm, or resembling an arm in shape, position, or function.n. Figuratively, power; might; strength; authority: as, the secular arm.n. Hence That on which one relies for support or assistance; a prop; a stay.To take by the arm; also, to seize or hold in the arms.n. Milit.: A weapon.n. plural Armor; coverings for the body intended as defenses against weapons of war.n. A branch of the military service, as cavalry or artillery: as, the enemy was strong in artillery, but we were weak in that arm.n. Hence plural The use of weapons; military occupations; war.n. plural Deeds or exploits of war.n. In law, anything which a man takes in his hand in anger to strike or assault another.n. plural In botany, anything that serves as a defense to a plant, as prickles, thorns, or spines.n. plural In falconry, the legs of a hawk from the thigh to the foot.n. plural The heraldic bearings of an individual or a community, consisting of some device in heraldic tinctures (see tincture) borne on a shield, generally with the addition of a crest and sometimes with supporters.n. Synonyms Arm, Weapon. Arm is especially applied to those things which are designed for fighting and recognized as such; it includes means of defense as well as of offense. Weapon applies to any means of offense made for the purpose or (as a scythe, chisel, or hammer) used for the nonce.To furnish or equip with weapons for offense or defense: as, to arm the militia.To cover or provide with whatever will add strength, force, or security: as, to arm the hilt of a sword; to arm a man-of-war with armor-plates.To furnish with means of defense; prepare for resistance; fortify.To provide with the requisite appliances or authority for any work or undertaking: as, armed with axes and alpenstocks, we started out; armed with a warrant.To fit or prepare (a thing) for any specific purpose or effective use: as, to arm a hook in angling; to arm a dressing in surgery.To provide one's self with arms, weapons, or means of attack or resistance; take arms: as, the nations arm for war.n. In violin-playing, the arm or its action in reference to the style of bowing: as, he plays with a good arm.n. In archery, the longitudinal half of a bow, extending from the handle to the end of the bowstaff: limb: classified as upper and lower arm, according to their relative position when the bow is held perpendicularly, as in shooting.n. At a disadvantage: as, to work at arm's length.