keep/break your word

break one's word

not to do what one said one would do; not to keep one's promise. (Compare this with keep one's word.) Don't say you'll visit your grandmother if you can't go. She hates people to break their word. If you break your word, she won't trust you again.
See also: break, word

keep one's word

to uphold one's promise; to do as one says. (The opposite of break one's word.) I told her I'd be there to pick her up, and I intend to keep my word. Keeping one's word is necessary in the legal profession.
See also: keep, word

keep/break your ˈword

do/fail to do what you have promised: Do you think she’ll break her word and tell everyone?
See also: break, keep, word