forlornyoudaoicibaDictYouDict[forlorn 词源字典]
forlorn: [12] Forlorn began life as the past participle of Old English forlēosan ‘lose completely, forfeit, abandon’, a compound verb formed in prehistoric Germanic times from the intensive prefix *fer- and *leusan (a relative of modern English lose). It retains some of its early connotations of being ‘abandoned’, but the main modern sense ‘miserable, downcast’ developed in the 14th century.

The forlorn of forlorn hope [16], incidentally, is a translation of the related Dutch verloren ‘lost’, but hope has no etymological connection with English hope. It is simply an anglicization of Dutch hoop ‘troop, band’ (to which English heap is related). The word was originally used for a squad of soldiers sent out on a very dangerous mission, with little hope that they would return.

The modern sense ‘hopeless undertaking’ developed in the 17th century, ‘misguided hope’ probably even more recently.

=> lose[forlorn etymology, forlorn origin, 英语词源]
forlorn (adj.)youdaoicibaDictYouDict
mid-12c., forloren "disgraced, depraved," past participle of obsolete forlesan "be deprived of, lose, abandon," from Old English forleosan "to lose, abandon, let go; destroy, ruin," from for- "completely" + leosan "to lose" (see lose). In the Mercian hymns, Latin perditionis is glossed by Old English forlorenisse. OED's examples of forlese end in 17c., but the past participle persisted. Sense of "forsaken, abandoned" is 1530s; that of "wretched, miserable" first recorded 1580s.

A common Germanic compound (cognates: Old Saxon farilosan, Old Frisian urliasa, Middle Dutch verliesen, Dutch verliezen, Old High German virliosan, German verlieren, Gothic fraliusan "to lose").

In English now often in forlorn hope (1570s), which is a partial translation of Dutch verloren hoop, in which hoop means "troop, band," literally "heap," and the sense of the whole phrase is of a suicide mission. The phrase more often than not is used in English as if it meant "a faint hope, and the misuse has colored the meaning of forlorn. Related: Forlornly; forlornness.