Definition of "arm" []

• An upper limb of the human body, connecting the hand and wrist to the shoulder. (noun)
• A part similar to a human arm, such as the forelimb of an animal or a long part projecting from a central support in a machine. (noun)
• Something, such as a sleeve on a garment or a support on a chair, that is designed to cover or support the human arm. (noun)
• A relatively narrow extension jutting out from a large mass: an arm of the sea. See Synonyms at branch. (noun)
• An administrative or functional branch, as of an organization. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "Although he cannot lift his arm without help, a simple ‘arm rocker’ made of foam plastic lets him move it in all directions."
• "We can readily understand that the use of an organ like the arm will affect it in such a way as to produce changes in its protoplasm, but we can hardly imagine that such use of the _arm_ would produce any change in the hereditary substance which is stored in the reproductive organs."
• "(ALBERT _and_ ALICE, FRED _and_ VICKEY _stand arm in arm_, L.)"