(anatomy) arm / ability; skill; talent

arm

use one thing for many purposes / work someone hard

to use one's head

(idiomatic) to be at a loss

behind, after

(spatially) the back, the rear, behind / (temporally) later, afterwards, some time after the present / the rest

one's backside / the back, the rear (both spatially and temporally)

the rear, back, or backside of something / the rearward or backward direction / the portion of a palace where a queen or other female imperial consort lives

later, afterwards, some time after the present