'hacker' definitions:

Definition of 'hacker'

(from WordNet)
noun
Someone who plays golf poorly
noun
A programmer who breaks into computer systems in order to steal or change or destroy information as a form of cyber- terrorism [syn: hacker, cyber-terrorist, cyberpunk]
noun
A programmer for whom computing is its own reward; may enjoy the challenge of breaking into other computers but does no harm; "true hackers subscribe to a code of ethics and look down upon crackers"
noun
One who works hard at boring tasks [syn: hack, drudge, hacker]

Definition of 'hacker'

From: GCIDE
  • hacker \hack"er\ (h[a^]k"[~e]r), n. One who, or that which, hacks. Specifically: A cutting instrument for making notches; esp., one used for notching pine trees in collecting turpentine; a hack. [1913 Webster]