hacker

Short definition from Wiktionary

Noun

1. 1
   Someone who hacks.
2. 2
   Someone who hacks: One who cuts with heavy or rough blows.
3. 3
   Someone who hacks: One who is inexperienced or unskilled at a particular activity, especially (sports, originally and chiefly golf), a sport such as golf or tennis.
4. 4
   Someone who hacks: One who is expert at programming and solving problems with a computer.
5. 5
   One who is expert at programming and solving problems with a computer: One who applies a novel method, shortcut, skill, or trick to something to increase ease, efficiency, or productivity.
6. 6
   Someone who hacks: One who uses a computer to gain unauthorized access to data stored in, or to carry out malicious attacks on, computer networks or computer systems.
7. 7
   Someone who hacks: Synonym of hackster (“a violent bully or ruffian; also, an assassin, a murderer”).
8. 8
   Something that hacks; a device or tool for hacking; specifically, an axe used for cutting tree branches or wood.
9. 9
   Something that hacks; a device or tool for hacking; specifically, an axe used for cutting tree branches or wood: A fork-shaped tool used to harvest root vegetables.
10. 10
    One who operates a taxicab; a cabdriver.

Verb

1. 1
   To speak with a spasmodic repetition of vocal sounds; to stammer, to stutter; also, to mumble and procrastinate in one's speech; to hem and haw.

Proper noun

1. 1
   A surname.