Put out. "One down" means one out has been made in the inning (two more to go in the inning). "One up (and) one down" means the first batter in the inning was out. "Two down" means two outs have been made in the inning (one more to go). "Two up (and) two down": the first two batters of the inning were retired (made outs). "Three up, three down": side retired in order.