derf

noun: An inept or foolish person, someone who doesn't use their head. On the PLATO computer system of the 1970s (which in many ways foreshadowed the Internet), a derf was one who left their computer terminal without logging out.

verb: On PLATO, a prank played on a derf. Sending out unpleasant or embarrassing messages under the handle (or "signon") of a person who'd forgotten to log out. Or ruining programs they've been working on.

noun: Wow, "Melvin of MIT" is a real derf! Look, he just walked out and left his terminal logged in.

verb: Hey Melvin, I just tried to run one of your programs and it looks like somebody got into it and put in a bunch of porn. Looks like you got derfed!

by Jay Young March 8, 2008

Derf

another way to say the word "duh" almost like obviously

Person 1: Wait why are we going to the mall?
Person 2: To go shopping, derf!!!

by yeah3xyeah3xyeah3x March 28, 2011

Derf

One stupid ass fucked up bitch, who doesnt know what she wants, lies all the time, tells you she likes you... but then sometimes wants to get on other people...

Man... she is such a Derf!

by Derf Hater July 12, 2006

derf

a retartedly, annoying white girl; usually very ugly

that stalker gurl is a mad derf

by Anonymous July 12, 2006

Dorfing

Cumming on your own chest and letting it dry repeating multiple days in a row until you have a giant cum mass on your torso

I've started Dorfing and my shirt is glued to my chest

by Stephen B May 31, 2017

derf

The reverse of the name "Fred". Commonly used by people who are either trying to be silly, those who think that it's a cool name and didn't like being labeled a "Fred", and those who truly think that it's a great pseudonym and no one will ever figure it out.

Overheard at a trekkie convention:

Fred: "Dude, I'm so awesome, I'm gonna reverse my name and call myself Derf."
Clueless friend: "Dude, that's awesome!!!"

by Octoboi July 30, 2007

dorf

mack.

A: DORF!
B: Oh so mack
A: Yeah, pretty much

by ihfbidfbifbuv September 24, 2011