What does "arm" mean?

Arm: Anything resembling an arm; as, (a) The fore limb of an animal, as of a bear. (b) A limb, or locomotive or prehensile organ, of an invertebrate animal. (c) A branch of a tree. (d) A slender part of an instrument or machine, projecting from a trunk, axis, or fulcrum; as, the arm of a steelyard. (e) (Naut) The end of a yard; also, the part of an anchor which ends in the fluke. (f) An inlet of water from the sea. (g) A support for the elbow, at the side of a chair, the end of a sofa, etc.

Additional senses

  1. 2.Fig.: Power; might; strength; support; as, the secular arm; the arm of the law. To whom is the arm of the Lord revealed Isa. lii.
  2. 3.Arm's end, the end of the arm; a good distance off. Dryden. -- Arm's length, the length of the arm. -- Arm's reach, reach of the arm; the distance the arm can reach. -- To go (or walk) arm in arm, to go with the arm or hand of one linked in the arm of another. "When arm in armwe went along." Tennyson. -- To keep at arm's length, to keep at a distance (literally or figuratively); not to allow to come into close contact or familiar intercourse. -- To work at arm's length, to work disadvantageously.
  3. 4.(a) A branch of the military service; as, the cavalry arm was made efficient. (b) A weapon of offense or defense; an instrument of warfare; -- commonly in the pl.
  4. 5.To take by the arm; to take up in one's arms. [Obs.] And make him with our pikes and partisans A grave: come, arm him. Shak. Arm your prize; I know you will not lose him. Two N. Kins.
  5. 6.To furnish with arms or limbs. [R.] His shoulders broad and strong, Armed long and round. Beau. & Fl.
  6. 7.To furnish or equip with weapons of offense or defense; as, to arm soldiers; to arm the country. Abram . . . armed his trained servants. Gen. xiv.
  7. 8.4. To cover or furnish with a plate, or with whatever will add strength, force, security, or efficiency; as, to arm the hit of a sword; to arm a hook in angling.
  8. 9.Fig.: To furnish with means of defense; to prepare for resistance; to fortify, in a moral sense. Arm yourselves . . . with the same mind. 1 Pet. iv.
  9. 10.To arm a magnet, to fit it with an armature.
  10. 11.To provide one's self with arms, weapons, or means of attack or resistance; to take arms. " 'Tis time to arm." Shak.

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