/ Dictionary / Index M mail-order house: Meaning and Definition of Find definitions for: mail'-order house" Pronunciation: [key] a retail firm that conducts its business by receiving orders and shipping its merchandise through the mail and that supplies its customers with catalogs, circulars, etc. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. mail order mail-out Related Content Daily Word Quiz: soporific Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language