poundyoudaoicibaDictYouDict[pound 词源字典]
pound: English has three distinct words pound. The measure of weight and unit of currency [OE] goes back ultimately to Latin pondō ‘12- ounce weight’, a relative of pondus ‘weight’ (source of English ponder) and pendere ‘weigh’ (source of English pension and poise). It was borrowed into prehistoric Germanic as *pundo, which has evolved into German pfund.

Dutch pond, Swedish pund, and English pound. Its monetary use comes from the notion of a ‘pound’ weight of silver. Pound ‘enclosure’ [14] is of unknown origin. It existed in Old English times in the compound pundfald, which has become modern English pinfold, and pond is a variant form of it. Pound ‘crush’ [OE] is almost equally mysterious.

In Old English it was pūnian (it did not acquire its final d until the 16th century, in fact), and it has been traced back to a Germanic *pūn-, which also produced Dutch puin ‘rubbish’.

=> pendant, pension, poise, ponder; pinfold, pond[pound etymology, pound origin, 英语词源]
pound (n.1)youdaoicibaDictYouDict
measure of weight, Old English pund "pound" (in weight or money), also "pint," from Proto-Germanic *punda- "pound" as a measure of weight (source of Gothic pund, Old High German phunt, German Pfund, Middle Dutch pont, Old Frisian and Old Norse pund), early borrowing from Latin pondo "pound," originally in libra pondo "a pound by weight," from pondo (adv.) "by weight," ablative of *pondus "weight" (see span (v.)). Meaning "unit of money" was in Old English, originally "pound of silver."

At first "12 ounces;" meaning "16 ounces" was established before late 14c. Pound cake (1747) so called because it has a pound, more or less, of each ingredient. Pound of flesh is from "Merchant of Venice" IV.i. The abbreviations lb., £ are from libra, and reflect the medieval custom of keeping accounts in Latin.
pound (n.2)youdaoicibaDictYouDict
"enclosed place for animals," late 14c., from a late Old English word attested in compounds (such as pundfald "penfold, pound"), related to pyndan "to dam up, enclose (water)," and thus from the same root as pond. Ultimate origin unknown; some sources indicate a possible root *bend meaning "protruding point" found only in Celtic and Germanic.
pound (v.)youdaoicibaDictYouDict
"hit repeatedly," from Middle English pounen, from Old English punian "crush, pulverize, beat, bruise," from West Germanic *puno- (cognates: Low German pun, Dutch puin "fragments"). With intrusive -d- from 16c. Sense of "beat, thrash" is from 1790. Related: Pounded; pounding.