someone's word is law

: some person : somebody

: a speech sound or series of speech sounds that symbolizes and communicates a meaning usually without being divisible into smaller units capable of independent use

: the entire set of linguistic forms produced by combining a single base with various inflectional elements without change in the part of speech elements

: a written or printed character or combination of characters representing a spoken word

: to express in words : phrase

: speak

: a binding custom or practice of a community : a rule of conduct or action prescribed (see prescribe 1a) or formally recognized as binding or enforced by a controlling authority

: the whole body of such customs, practices, or rules

: common law

: litigate

: to sue or prosecute at law