... bunk, not taking the first step of an eider? (6)
I believe the answer is:
waddle
'first step of an eider?' is the definition.
I can't judge whether this definition defines the answer.
'bunk not taking the' is the wordplay.
'bunk' becomes 'twaddle' (I've seen this before).
'not taking' indicates named letters should be taken away.
'the' becomes 't' (the is pronounced as a 't' sound in some dialects).
'twaddle' with 't' taken out is 'WADDLE'.
Can you help me to learn more?
(Other definitions for waddle that I've seen before include "Duck-like walk" , "Clumsy swaying walk" , "Walk with a clumsy sway" , "get moving, if somewhat slowly" , "Move like a duck" .)