underfoot (adv.)youdaoicibaDictYouDict[underfoot 词源字典]
c. 1200, underfot "under the feet," from under + foot (n.). Compare similarly formed Middle Dutch ondervoete. As an adjective, attested from 1590s; in reference to persons, "continually in the way," it is recorded from 1891. Middle English under fot meant "vanquished, overcome."[underfoot etymology, underfoot origin, 英语词源]