What a European would call these flipping feckless displays! (5)
I believe the answer is:
moose
'would call these flipping feckless displays' is the definition.
The definition suggests an adverb but the answer is not.
'what a european' is the wordplay.
I cannot quite see how this works, but
'european' could be 'e' (abbreviation e.g. EU) and 'e' is found in the answer.
The remaining letters 'moos' is a valid word which might be clued in a way I don't understand.
This explanation may well be incorrect...
(Other definitions for moose that I've seen before include "Large US deer" , "US deer with enormous antlers" , "Ungulate" , "North American deer" , "Large northern deer" .)