Essentially downy, we float freely around river? (9)

'essentially downy we float freely around river?' is the definition.
I can't judge whether this definition defines the answer.

'essentially downy we float freely around river?' is the wordplay.
'essentially' indicates the central letters.
'freely' indicates anagramming the letters.
'around' indicates putting letters inside.
'river?' becomes 'r' (abbreviation for river).
The centre of 'downy' is 'w'.
'w'+'we'+'float'='wwefloat'
'wwefloat' is an anagram of 'watefowl'.
'watefowl' going around 'r' is 'WATERFOWL'.

Can you help me to learn more?