国际日期变更线/ 國際日期變更線 guójìrìqībiàngēngxiàn (also guójìrìqíbiàngēngxiàn) International Date Line
An imaginary line on the Earth's surface, roughly following the 180th meridian, where the date changes by one day; also known as 日界线 rìjièxiàn and in Taiwan as 国际换日线 guójìhuànrìxiàn