noun

The rear surface of the human body from the shoulders to the hips.

he lay on his back

adverb

Toward the rear; in the opposite direction from the one that one is facing or traveling.

she moved back a pace

backwards,behind one,to one’s rear,rearwards

verb

Give financial, material, or moral support to.

he had a newspaper empire backing him

sponsor,finance,put up the money for,fund,subsidize,underwrite,promote,lend one’s name to,be a patron of,act as guarantor of,support

adjective

Of or at the back of something.

the back garden

rear