Arm

Arm is each of the upper limbs of the human body from the shoulder to the elbow. In birds, it is the base of the wing from the carpal joint to where it joins the body, often used in describing seabirds and birds of prey. In vertebrate animals, arm is each of the forelimbs. In invertebrate animal, it is a flexible limb, such as in an octopus.

A sleeve of a garment, a thing resembling an arm in form or function, such as a side part of a chair or other seat on which a sitter's arm can rest, a large branch of a tree, or each of the lines enclosing an angle is also called an arm.