Pronunciation: (un"dur-bid'),[key] —v.t.,-bid, -bid•ding. 1. to bid less than (another bid) or less than the bid of (another bidder), esp. in seeking a contract to be awarded to the lowest bid or bidder; make an offer at a lower price than.
2. Cards.to bid less than the value or worth of (a contract or hand).
—v.i. to bid lower than another or too low for the value of something.