A staircase in which each flight turns sharply so as to ascend parallel to the flight below it.
Early 18th century; earliest use found in Ephraim Chambers (?1680–1740), encyclopaedist.
英汉双解词典包含464360条英汉词条,基本涵盖了全部常用单词的翻译及用法,是英语学习的有利工具。