Wading bird in small list (5)
I believe the answer is:
stilt
'wading bird' is the definition.
(stilt is a kind of wading bird)
'small list' is the wordplay.
'small' becomes 's' (abbreviation - e.g. clothes size).
'list' becomes 'tilt' (both can mean to lean).
's'+'tilt'='STILT'
'in' is the link.
(Other definitions for stilt that I've seen before include "laboured and unnatural in the past" , "Wading bird; post" , "bird found on shore" , "Supporting column driven into the ground - wading bird" , "Flier" .)