What is an arm?

An arm is the thing attached to your shoulder and that has a hand attached to it.

An arm can also be used to describe structure, for example:

  • the long arm of the law
  • the legislative arm of government
  • a smaller area of water (sea, gulf) extending from a larger body of water

An arm can also exist in certain machinery where a part is similar to the joint movements of a human arm.

Note: "A foot" is also used to describe parts, for example, a "zipper foot" on a sewing machine. A "leg" is used as a descriptor, for example, "On the last leg of our journey the car overheated."