padlock (n.)youdaoicibaDictYouDict[padlock 词源字典]
"removable lock," late 15c., from lokke (see lock (n.)), but the first element is of unknown origin.[padlock etymology, padlock origin, 英语词源]
padlock (v.)youdaoicibaDictYouDict
1640s, from padlock (n.). Related: Padlocked; padlocking.