When Someone who usually has nothing to do, usually because they're unemployed, suddenly has something to do for that day. That one thing, no matter how meaningless becomes the big deal of the day.
Person 1 - "Hey what did you do today?"

Person 2 - "Went out to buy some milk."

Person 1 - "That was your big deal of the day huh?"

Person 2 - "Shut the fuck up before I beat your ass!!"

Person 1 - "Are you sure you can handle another Big Deal of The Day?"

Person 2 - "Hmmm, Maybe not."
by Jachzehn June 13, 2009
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