LD Share definition Flag loser department basically school! a school that no one likes and is full of loserish nobs(people that really have no life whatsoever) 'DUDE, we got LD tomorrow, i really feel like skippin' or 'c you at the LD on monday' LD by 3'buenos'14's December 26, 2009 0 0 Get merch Get the LD mug. Buy Now — $32.95 See more merch