by nick April 28, 2006

The error function. Computer programs such as Mathematica and Maple incorrectly evaluate about 95% of integrals taken over all space. When the program fails to recognize an integral, it automatically spits out "erf" for an unknown reason.

Person 1: Dude, we have a Quantum Mechanics homework set due in 30 minutes, & I can't figure out how to evaluate this integral.

Person 2: Don't worry, we'll put it into Maple!

Maple: Erf erf erf erf erf...

Professor: epic fail.

Person 2: Don't worry, we'll put it into Maple!

Maple: Erf erf erf erf erf...

Professor: epic fail.

by MorvAreed April 14, 2009

by droneaccount808 November 17, 2010

Word used to express disappointed yet accepted state of undesired feeling, situation or physical state. A vocal statement of realization - that things are f-ed up and you can't change it. "That's erf'ed up."

You just woke up from a gigantic night of partying... realize head is pounding and stomach about to hurl. Instead of groaning, which could mean anything, you mutter "ERF!!" and those laying around the room also waking with hangovers acknowledge your state and also chime in with an affirmative, "ERF!".

by BleenieTheCat October 14, 2005

by Kevin Cheung July 19, 2005