1) Back out 2) Back out a commitment 3) Back out of a deal 4) Back out on a promise 5) Backpedal 6) Blunder at bridge 7) Break a bridge rule 8) Break a promise 9) Break a rule in cards 10) Bridge accident 11) Bridge blunder 12) Bridge boner 13) Bridge boo-boo 14) Bridge goof 15) Bridge infraction 16) Bridge problem 1) Backout 2) Copout 3) Revoke 
• (v. i.) To revoke. • (v. t.) To deny; to disown. • (v. i.) To deny.
Re·nege' intransitive verb 1. To deny. [ Obsolete] Shak. 2. (Card Playing) To revoke. [ R.] Re·nege' transitive verb [ Late Latin renegare . See Renegade .] To deny; to disown. [ Obsolete] Shak. « All Europe high (all sorts of rights reneged ) Against the truth and thee unholy leagued.» Sylvester. 
Arbitrarily failing to perform a contract requirement such as delivery or payment.
In card games to renege is the allowable play of failing to follow suit when one does not have to follow suit.
[v] - fail to fulfill a promise or obligation
Renege refers to the situation that a signed or a verbal contract is not met. In other words, this occurs when one party breaks his or her agreement with another party.
[SAT terms] fail to fulfill a promise or obligation fail to fulfill a promise or obligation