late 14c., "make a deep, heavy, continuous sound," also "move with a rolling, thundering sound," also "create disorder and confusion," probably related to Middle Dutch rommelen "to rumble," Middle High German rummeln, Old Norse rymja "to shout, roar," all of imitative origin. Related: Rumbled; rumbling.
rumble (n.)
late 14c., from rumble (v.). Slang noun meaning "gang fight" is from 1946. Meaning "backmost part of a carriage" is from 1808 (earlier rumbler, 1801), probably from the effect of sitting over the wheels; hence rumble seat (1828).
ruler
ruling
ruly
rum
rumba
rumble
rumbustious
rumen
ruminant
ruminate
rumination