1. Fail to fulfil a promise or obligation
   "He went back on his word and didn't show up for the meeting";
   - renege, renege on, renegue on [Brit], renegue [Brit]

Derived forms: went back on, going back on, gone back on, goes back on

Type of: annul, countermand, lift, overturn, repeal, rescind, reverse, revoke, vacate