Ringer \Ring"er\, n.1. One who, or that which, rings; especially, one who rings chimes on bells.
2. (Mining) A crowbar. --Simmonds.
Source: Webster's Revised Unabridged Dictionary (1913)
Ringer \Ring"er\, n. (Horse Racing) A horse that is not entitled to take part in a race, but is fraudulently got into it.