A terse retort. A short sharp response to someone who is struggling to contain themselves and is pushing their insecurities outwards onto everyone else. A 'grundy response' should only be used with people who you have a baseline friendship and / or respect with as they are often quite harsh and may include profanity.

The term can also be used in a derogatory fashion when referring to anytime you responded negatively to someone who is asking you to do something (haha I gave him a grundy response)
At a relaxed social gathering at Tommy's house people are preparing for a large scale group dinner. Tommy is stressed because he wants everything to be perfect, as a result he is pushing his stress outwards onto everyone else. Jim is making gravy for the above mentioned dinner:

Tommy: Jim is the gravy ready?
Jim: Not yet, I'm working on it, just need a little more time to make it good enough.
(30 seconds later)
Tommy: Jim, the gravy, is it ready? What's happening!?
Jim: I'm working on it, I want to do a good job, it should be ready soon.
(10 seconds later)
Tommy: Look, Jim, the consensus is that we don't care how good the gravy is.
Jim: Well, the consensus can go fuck itself Tommy <- Grundy response

At first look the Grundy response seems harsh, but in reality Jim is aware of how relaxed the situation is and that Tommy is just running around talking a lot but getting very little done other than stressing people out. The grundy response is used to snap him back into the reality of the situation.
by slackjawedfrigate April 25, 2013
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