Completely wrap a small duck's walk (7)
I believe the answer is:
swaddle
'completely wrap' is the definition.
'swaddle' can be an answer for 'wrap' (I've seen this in another clue). I'm not certain of the 'completely' bit.
'a small duck's walk' is the wordplay.
'a small duck's' becomes 's' (I can't justify this - if you can you should believe this answer much more).
'walk' becomes 'waddle' (waddling is a kind of walking).
's'+'waddle'='SWADDLE'
Can you help me to learn more?
(Other definitions for swaddle that I've seen before include "Wind bandages round" , "Wrap with bandages" , "Wrap in cloth" , "Bind tight with clothes" , "Wrap up well" .)