Real Dictionary

nobble
verb: If someone nobbles a racehorse, they deliberately harm it, often using drugs, in order to prevent it from winning a race.
verb: If someone nobbles an important group of people such as a committee, they offer them money or threaten them in order to make them do something.
verb: If someone nobbles your plans or chances of succeeding, they prevent you from achieving what you want.

nobble in American English
to disable (a horse), as by drugging to keep it from winning a race
transitive verb: to drug or disable (a race horse) to prevent its winning a race

nobble in British English
to disable (a racehorse), esp with drugs