sellyoudaoicibaDictYouDict[sell 词源字典]
sell: [OE] The underlying etymological meaning of sell is ‘give up, hand over’, but gradually the notion of handing something over in exchange for something else, particularly money, led to its present-day sense. Both meanings co-existed in Old English, but the original one had largely died out by the 14th century. The word comes from a prehistoric Germanic *saljan, which also produced Swedish sälga and Danish sælge ‘sell’. The noun sale is a product of the same base.
=> sale[sell etymology, sell origin, 英语词源]
sell (v.)youdaoicibaDictYouDict
Old English sellan "to give, furnish, supply, lend; surrender, give up; deliver to; promise," from Proto-Germanic *saljan "offer up, deliver" (cognates: Old Norse selja "to hand over, deliver, sell;" Old Frisian sella, Old High German sellen "to give, hand over, sell;" Gothic saljan "to offer a sacrifice"), ultimately from PIE root *sel- (3) "to take, grasp."

Meaning "to give up for money" had emerged by c. 1000, but in Chaucer selle still can mean "to give." Students of Old English learn early that the word that looks like sell usually means "give." An Old English word for "to sell" was bebycgan, from bycgan "to buy."

Slang meaning "to swindle" is from 1590s. The noun phrase hard sell is recorded from 1952. To sell one's soul is from c. 1570. Sell-by date is from 1972. To sell like hot cakes is from 1839. Selling-point attested from 1959.

To sell (someone) down the river figuratively is by 1927, probably from or with recollection of slavery days, on notion of sale from the Upper South to the cotton plantations of the Deep South (attested in this literal sense since 1851).