supporter

a person who backs a politician or a team etc.; "all their supporters came out for the game"; "they are friends of the library"

someone who supports or champions something

a person who contributes to the fulfillment of a need or furtherance of an effort or purpose; "my invaluable assistant"; "they hired additional help to finish the work"

a band (usually elastic) worn around the leg to hold up a stocking (or around the arm to hold up a sleeve)

a support for the genitals worn by men engaging in strenuous exercise