chomp: vi. To {lose}; specifically, to chew on something of which more was bitten off than one can

:chomp: vi. To {lose}; specifically, to chew on something of
which more was bitten off than one can. Probably related to
gnashing of teeth. See {bagbiter}.

A hand gesture commonly accompanies this. To perform it, hold the
four fingers together and place the thumb against their tips. Now
open and close your hand rapidly to suggest a biting action (much
like what Pac-Man does in the classic video game, though this
pantomime seems to predate that). The gesture alone means `chomp
chomp' (see "{Verb Doubling}" in the "{Jargon
Construction}" section of the Prependices). The hand may be
pointed at the object of complaint, and for real emphasis you can
use both hands at once. Doing this to a person is equivalent to
saying "You chomper!" If you point the gesture at yourself, it
is a humble but humorous admission of some failure. You might do
this if someone told you that a program you had written had failed
in some surprising way and you felt dumb for not having anticipated
it.
-- The AI Hackers Dictionary