Date Line
noun/ˈdeɪt laɪn/
/ˈdeɪt laɪn/
(also the International Date Line)
[singular]- the imaginary line that goes from north to south through the Pacific Ocean. The date on the west side is different by one day from that on the east side.
日界线（联结地球南北极的假想线。向东航行越过此线须减去一天，向西须增加一天）