Breadcrumb Home > Dictionary > Index L law merchant: Meaning and Definition of Find definitions for: law' mer'chant Pronunciation: [key] the principles and rules, drawn chiefly from custom, determining the rights and obligations of commercial transactions; commercial law. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. lawman lawn ✖ Related Content Daily Word Quiz: rococo Analogy of the Day: Today’s Analogy Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language