a person or thing that supports.

an adherent, follower, backer, or advocate.

a device, usually of elastic cotton webbing, for supporting some part of the body, esp. a jockstrap.

a garter, esp. one attached to a garter belt or girdle.

Heraldry . either of two human or animal figures flanking and supporting an escutcheon in an achievement of arms.

noun

adherent , cohort , disciple , henchman , minion , partisan , satellite , backer , benefactor , contributor , friend , sponsor , abettor , abider , advocate , ally , bearer , booster , brace , defender , exponent , follower , paraclete , patron , pillar , proponent , seconder , support , suspender , sustainer , upholder