go back on (something)(redirected from go back on something)
go back on (something)
To not do something one said one would do; to renege on something. People are beginning to worry that the president is going to go back on his promise of lowering taxes for lower-income families. You made a commitment to support our project, and now you've gone back on your word!
go back on
Fail to honor or keep, as in You can't go back on your word, or One should never go back on a promise. [Mid-1800s]