Synonyms for Big Dipper (same or very similar meaning)
WordNet sense 1 (a group of seven bright stars in the constellation Ursa Major):
dipper, plough, wagon, wain, Charles's WainWordNet sense 2 (elevated railway in an amusement park (usually with sharp curves and steep inclines)):
chute-the-chute, roller coasterFrom the ODE community, based on WordNetadd/edit