Definition of "heeler"

heeler

noun
plural heelers
1. A gamecock that strikes well with its heels or spurs.
2. A quick runner.
  Quotations
  That a crowd of Sydney stealers,Jockeys, pugilists and spielersBrought some horses, real heelers,Came and put us through.
  1891, Banjo Paterson, An Evening in Dandaloo
3. A dog that readily comes to heel.
  Quotations
  If your dog is a good heeler, you'll find some competition in the obedience ring.
  1999, Ted Baer, Communicating with Your Dog: A Humane Approach to Dog Training
4. (US, slang, politics, dated) A dependent and subservient hanger-on of a political patron.
  Quotations
  The army of hungry heelers who do their bidding.
  1886, Theodore Roosevelt, “Machine Politics”, in The Century
5. The rodeo performer who ropes the steer by its hind feet after the header has turned it.