Definition of hardballs:
(n) :
(figurative) Tough or ruthless behavior, especially in combat, politics or business.
(adj) :
Being or exhibiting tough or ruthless behavior, especially in combat, politics or business.
(v) :
(informal, transitive) To exhibit tough and ruthless behavior towards another individual.
(n) :
(ball games) In baseball, a type of ball and baseball game, as opposed to softball.