Stink filling middle of dustbins is something in hand (5)
I believe the answer is:
thumb
'in hand' is the definition.
(I know that thumb is part of hand)
'stink filling middle of dustbins' is the wordplay.
'stink' becomes 'hum' (I've seen this in other cluesasomething with a bad).
'filling' is an insertion indicator.
'middle of' says to take the centre.
The middle of 'dustbins' is 'tb'.
'hum' put within 'tb' is 'THUMB'.
'is something' acts as a link.
I am not very happy about this link. Some or all of it may be part of another bit of the clue.
Can you help me to learn more?
(Other definitions for thumb that I've seen before include "Digit used in getting free rides from motorists" , "One opposed to other manual workers" , "Tom's digit" , "Travel by . . . . . - hitchhike" , "Stubby digit?" .)