From Longman Dictionary of Contemporary Englishbig dipperˌbig ˈdipper noun [countable] 1 DLO British English old-fashioned a small railway in a funfair, with steep slopes and sharp curves to give an exciting ride2 → the Big Dipper
Examples from the Corpus
big dipper• The descent, like a big dipper, is exhilarating but perfectly safe. 