'Flat-footed' definitions:

Definition of 'flat-footed'

From: WordNet
adjective
With feet flat on the ground; not tiptoe
adjective
Unprepared and unable to react quickly; "the new product caught their competitors flat-footed"
adjective
Having broad flat feet that usually turn outward; "a slow flat-footed walk"
adjective
Without reservation; "a flat-footed refusal"

Definition of 'Flat-footed'

From: GCIDE
  • Flat-footed \Flat"-foot`ed\, a.
  • 1. Having a flat foot, with little or no arch of the instep; suffering from fallen arches. [WordNet sense 3] [1913 Webster]
  • 2. Firm-footed; determined. [Slang, U.S.] [1913 Webster]
  • 3. clumsy; amateurish; pedestrian; unimaginative; plodding; as, flatfooted prose. [PJC]
  • 4. Without reservation; without evasion or compromise; firm; as, a flat-footed refusal; a flatfooted denial. [WordNet sense 4]
  • Syn: downright, forthright, foursquare, head-on, straightforward. [PJC]
  • 5. With feet flat on the ground; not tiptoe. [WordNet sense 1] [WordNet 1.5]
  • 6. Unprepared and unable to react quickly; as, the new product caught their competitors flat-footed. [WordNet sense 2]
  • Syn: unready. [WordNet 1.5]
  • To catch (one) flatfooted to catch (a person) unprepared; to catch (a person) by surprise. [PJC]