motherfucker

Short definition from Wiktionary

Interjection

1. 1
   Expressing dismay, discontent, or surprise.

Noun

1. 1
   An extremely contemptible, vicious or mean person.
2. 2
   Any person, often but not always with the connotation that the person is disliked or is threatening.
3. 3
   An extremely intense experience, often but not always negative.
4. 4
   An extremely intense experience, often but not always negative: To an extreme degree.
5. 5
   A good very close friend or relative.
6. 6
   One who engages in incest with their mother.
7. 7
   One who engages in sex with a mother, not necessarily one's own.