ringer

(noun) a person who rings church bells (as for summoning the congregation). Synonyms: toller, bell ringer.

(noun) a person who is almost identical to another. Synonyms: dead ringer, clone.

(noun) a contestant entered in a competition under false pretenses.

(noun) (horseshoes) the successful throw of a horseshoe or quoit so as to encircle a stake or peg.