/ Dictionary / Index M master-at-arms: Meaning and Definition of Find definitions for: mas•ter-at-arms Pronunciation: (mas'tur-ut-ärmz', mä'stur-), [key] — pl. mas•ters-at-arms. an officer of a fraternal organization, veterans' society, or the like, empowered to maintain order, exclude unauthorized persons, etc. a petty officer who has various duties, such as keeping order on the ship, taking charge of prisoners, etc. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: master-at-arms (Thesaurus) master alloy master bath Related Content Daily Word Quiz: eureka Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language