1. [n]  the act of losing or surrendering something as a penalty for a mistake or fault or failure to perform etc.
2. [n]  a penalty for a fault or mistake that involves losing or giving up something; "the contract specified forfeits if the work was not completed on time"
3. [n]  something that is lost or surrendered as a penalty;
4. [adj]  surrendered as a penalty
5. [v]  lose or lose the right to by some error, offense, or crime

Forfeit
A racing reporter looks into the death of his colleague who had written a series of columns about can`t lose horses. Someone would lose however, when the horses mysteriously disappeared immediately after the columns ran.

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1. \For"feit\, n. [OE. forfet crime, penalty, F. forfait
   crime (LL. forefactum, forifactum), prop. p. p. of forfaire
   to forfeit, transgress, fr. LL. forifacere, prop., to act
   beyond; L. foris out of doors, abroad, beyond + facere to do.
   See {Foreign}, and {FAct}.]
   1. Injury; wrong; mischief. [Obs. & R.]
            To seek arms upon people and country that never did
            us any forfeit.                       --Ld. Berners.
   2. A thing forfeit or forfeited; what is or may be taken from
      one in requital of a misdeed committed; that which is
      lost, or the right to which is alienated, by a crime,
      offense, neglect of duty, or breach of contract; hence, a
      fine; a mulct; a penalty; as, he who murders pays the
      forfeit of his life.
            Thy slanders I forgive; and therewithal Remit thy
            other forfeits.                       --Shak.
   3. Something deposited and redeemable by a sportive fine; --
      whence the game of forfeits.
            Country dances and forfeits shortened the rest of
            the day.                              --Goldsmith.
   

2. \For"feit\, a. [F. forfait, p. p. of forfaire. See
   {Forfeit}, n.]
   Lost or alienated for an offense or crime; liable to penal
   seizure.
         Thy wealth being forfeit to the state.   --Shak.
         To tread the forfeit paradise.           --Emerson.
   

3. \For"feit\, v. t. [imp. & p. p. {Forfeited}; p. pr. &
   vb. n. {Forfeiting}.] [OE. forfeten. See {Forfeit}, n.]
   To lose, or lose the right to, by some error, fault, offense,
   or crime; to render one's self by misdeed liable to be
   deprived of; to alienate the right to possess, by some
   neglect or crime; as, to forfeit an estate by treason; to
   forfeit reputation by a breach of promise; -- with to before
   the one acquiring what is forfeited.
         [They] had forfeited their property by their crimes.
                                                  --Burke.
         Undone and forfeited to cares forever!   --Shak.
   

4. \For"feit\, v. i.
   1. To be guilty of a misdeed; to be criminal; to transgress.
      [Obs.]
   2. To fail to keep an obligation. [Obs.]
            I will have the heart of him if he forfeit. --Shak.
   

5. \For"feit\, p. p. or a.
   In the condition of being forfeited; subject to alienation.
   --Shak.
         Once more I will renew His laps[`e]d powers, though
         forfeite.                                --Milton.