a. One that fails to win: the losers of the game.

b. A person who takes loss in a specified way: a graceful loser; a poor loser.

a. A person who is unable to be successful on a sustained basis: His mother considers his friends to be a bunch of losers.

b. One that loses opportunities or advantages: The losers in the latest round of budget cuts included retirees and pensioners.

c. One that is bad in quality: That book is a real loser.