Son not working making move furtively (5)
I believe the answer is:
sidle
'move furtively' is the definition.
(I've seen this before)
'son not working' is the wordplay.
'son' becomes 's'.
'not working' becomes 'idle' (I've seen this before).
's'+'idle'='SIDLE'
'making' acts as a link.
(Other definitions for sidle that I've seen before include "Move in furtive or timid manner" , "Slide (anag.)" , "Edge along furtively" , "Move in furtive manner, edge along" , "Walk crabwise" .)