ˌflat-ˈfooted BrE AmE adjective
1 . having flat feet
2 . informal moving in an awkward way SYN clumsy :
The defence looked flat-footed as Sutton scored easily.
3 . catch somebody flat-footed American English to surprise someone so that they cannot do something in the way they ought to SYN catch somebody off guard :
The President’s announcement seemed to catch Democrats flat-footed.