From Longman Dictionary of Contemporary Englishspiral staircaseˌspiral ˈstaircase noun [countable] DHTBBa set of stairs arranged in a circular pattern so that they go around a central point as they get higher
Examples from the Corpus
spiral staircase• He charged his customers a flat dollar for a trip down his spiral staircase to the foot of the cataract.• To find out what, one of us would have to slink down that narrow iron spiral staircase in the dark.• But then they began to climb up a narrow, spiral staircase, and she saw no more.• After the appropriate phone call, I am ask d to walk down an oak spiral staircase one floor.• She pulled herself back up the spiral staircase and made for the bathroom.• In the same building there is triple spiral staircase. 