arm (from shoulder to wrist); (fig.) assistant; helper

arms

forearm

armband

upper arm

actuator (arm of a lever)

lever arm (i.e. perpendicular distance from the fulcrum to the line of force)

linking arms

to swing one's arm widely and walk off, meaning not caring at all

tone-arm (tracking arm of gramophone)

crook of the arm

gibbon

robotic arm

muscular arms or fat arms, usually referring to the arms of women, derogatory; 麒麟 is a mythical chimerical creature in Chinese folklore

tattoo-covered arm; tattoo sleeve

arm strength

Orion spiral arm or local spur of our galaxy (containing our solar system)

arm

one-armed

to cross one's arms

arm span

a helping hand; literally an arm of force

(lit.) (having) three heads and six arms (idiom)