damyoudaoicibaDictYouDict[dam 词源字典]
dam: [12] Dam, appropriately enough for a word related to the human control of water-courses, seems to have been borrowed from Middle Dutch dam. It appears to have been a fairly widespread West and East Germanic word, subsequently borrowed into North Germanic, but its ultimate source is not known.
[dam etymology, dam origin, 英语词源]
dam (n.1)youdaoicibaDictYouDict
"water barrier," early 14c., probably from Old Norse dammr or Middle Dutch dam, both from Proto-Germanic *dammaz (cognates: Old Frisian damm, German Damm), which is of unknown origin.
dam (n.2)youdaoicibaDictYouDict
"animal mother," c. 1300, variant of dame (q.v.), also originally used, like that word, for "lady, mother;" but meanings diverged into separate spellings by 16c.
dam (v.)youdaoicibaDictYouDict
late 15c., from dam (n.1). Related: Dammed; damming.