someone's word is law
Definition of someone's word is law
—used to say that other people must do what someone says He'll listen to suggestions, but in the end, his word is law.
Word by Word Definitions
: some person : somebody
: something that is said
: talk, discourse
: the text of a vocal musical composition
: to express in words : phrase
Seen and Heard
What made you want to look up someone's word is law? Please tell us where you read or heard it (including the quote, if possible).