late 14c., as a type of diving bird, agent noun from dip (v.). As "a ladle or long-handled utensil for drawing liquid," from 1783, chiefly American English. Also "a Dunker, an Anabaptist" (1610s); "one who dips snuff" (1870). As the popular U.S. name for the asterism known in Britain as The Plough or Charles's Wain, attested by 1833, so called for the arrangement of the stars. Compare Big Dipper.