[flat-foo t-id]
  1. having flatfeet.
  2. taking or showing an uncompromising stand in a matter; firm and explicit: a flatfooted denial.
  3. clumsy or plodding; maladroit: flatfooted writing.
  1. catch one flatfooted, to catch one unprepared; surprise: The amount of the bill caught us flatfooted.

Origin of flatfooted

First recorded in 1595–1605; flatfoot + -ed3
Related formsflat·foot·ed·ly, adverbflat·foot·ed·ness, noun
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018