Waterfowl, bottom-up, floundered -- I emoted somewhat (5)
I believe the answer is:
eider
'waterfowl' is the definition.
(eider is a kind of waterfowl)
'bottom-up floundered i emoted somewhat' is the wordplay.
'bottom-up' says the letters should be written backwards (letters read from the bottom).
'somewhat' says the answer is hidden in the clue.
'redie' is hidden in the letters of 'floundered i emoted'.
'redie' in reverse letter order is 'EIDER'.
(Other definitions for eider that I've seen before include "Down-producing duck" , "Large sea duck" , "Sea bird" , "Duck providing fine down" , "Variety of duck" .)