A variant of "fucker" used on Canadian television, primarily "Royal Canadian Air Farce". Pre-teens have been known to use it when quoting, should the term "fucker" come up in the quotation.

A swimmer

The word "effers" was derived from some retarded kid by the name of Alor.
The word is usually used to express annoyance, disgust, surprise, anger, irritation, contempt, or disappointment...usually in a light-hearted manner.
(Lately, this word has been favorably used using squinted eyes, a scrunched nose, and a whispery, whiny voice, all while hunching the back slightly and is usually followed by the recipient with the traditional slow shake of the head, a stupid smirk and the low mutter of the word "geek.")

mother fucker; bitch/son of a bitch.

An insult.

Someone who owns you, especially in Counter-Strike, Starcraft, and Reversi.

FUCKER!
(F-er!)