WordNet (r) 3.0 (2006):
Big Dipper n 1: a group of seven bright stars in the constellation Ursa Major [syn: Big Dipper, Dipper, Plough, Charles's Wain, Wain, Wagon] 2: elevated railway in an amusement park (usually with sharp curves and steep inclines) [syn: roller coaster, big dipper, chute-the-chute]