un ‧ der ‧ foot /ˌʌndəˈfʊt $ -ər-/ BrE AmE adverb
1 . under your feet where you are walking
wet/firm/soft etc underfoot
The wet wood is very slippery underfoot.
2 . trample somebody/something underfoot
a) to crush someone or something on the ground by stepping heavily on them
b) to completely destroy someone or something