Lacking wings, asked all vets for any small bones (9)
I believe the answer is:
skeletons
'bones' is the definition.
'lacking wings asked all vets for any small' is the wordplay.
I cannot quite see how this works, but
'for' could be 'to' (eg both can mean 'in the opinion of') and 'to' is found within the answer.
'small' could be 's' (abbreviation - e.g. clothes size) and 's' is located in the answer.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for skeletons that I've seen before include "Frames of bodies" , "Lost knees (anag.)" , "Bony frameworks" , "Body frames" , "Frameworks of bone" .)