Mf

[Rihanna]

mf has 2 meanings, often used as:

(i) Mother Fucker
(ii) My Friend

definition (i) is more commonly seen in chatrooms; whereas definition (ii) seen in multiplayer games.

if someone uses mf towards you, its best to pretend you dont understand, so they will explain - either (i) or (ii). Since you dont want to just start insulting them.

[Sarah]

Motherfucker

[Hina Muqadas]

In the PC game Diablo2, mf stands for magic find. Magic find is when you go to monsters with good drops and keep killing them in hopes that they will drop a good item

[Lanell]

Stands for one of the following forms of motherfucker: motherfucker, [motherfucking], [motherfuck]. The form that is used [depends] on the context of the situation.