INTERNATIONAL DATE LINE

longitude line located at 180 degrees, longitude line that divides time zones so that one side is one one calendar day and the other side is on the next calendar day

The International Date Line (IDL), also known as just the Date Line, is an imaginary line on the surface of the Earth opposite the Prime Meridian which offsets the date as one travels east or west across it. Roughly along 180° longitude, with diversions to pass around some territories and island groups, it mostly corresponds to the time zone boundary separating +12 and −12 hours GMT (UT1). Crossing the IDL traveling east results in a day or 24 hours being subtracted, and crossing west results in a day being added.
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Noun
1. an imaginary line on the surface of the earth following (approximately) the 180th meridian
(synonym) dateline, date line
(hypernym) meridian, longitude, line of longitude

The line coinciding approximately with the anti-meridian of Greenwich, modified to avoid certain habitable land. In crossing this line there is a date change of one day. Also called "date line". 1/4/73

Ligne coïncidant approximativement avec l'antiméridien de Greenwich modifiée pour éviter certaines régions habitées. Au passage de cette ligne la date change d'un jour. Aussi appelée "ligne de changement de date". 1/4/73

Eng: international date line
Urdu: عالمی خطِّ تاریخ ۔ ایک نظری خَط جِس پر تاریخ بدل جاتی ہے ۔