dateline (n.)youdaoicibaDictYouDict[dateline 词源字典]
1880, imaginary line down the Pacific Ocean on which the calendar day begins and ends, from date (n.1) + line (n.). Meaning "line of text that tells the date and place of origin of a newspaper, article, telegram, etc." is from 1888.[dateline etymology, dateline origin, 英语词源]