DEAD GIVEAWAY

{n.} (stress on "give") 1. An open secret. * /By mid-afternoon, it was a dead giveaway who the new boss would be./ 2. A forced or sacrifice sale at which items are sold for much less than their market value. * /The Simpson's garage sale was actually a big giveaway./ 3. A gift; something one doesn't have to pay for. * /The tickets to the concert were a giveaway./