1 definition by YELDEP

Somebody who acts immature, lacks in banter and is generally an embarrassment to hang around with, due to this they tend to have no friends (other than sacks), it can also be said that sacks come in packs, as sacks tend to from groups of other sacks, having photo sessions where they take endless photos of themselves, then add them to facebook, or pretending to be drunk off one beer or a sip of wine! The list of sack activities are endless.
She had one wkd and told everyone she was mortal, what a fucking sack
by YELDEP June 18, 2011
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