General has chain for hanger-on (5)
I believe the answer is:
leech
'hanger-on' is the definition.
(leech can mean a hanger-on or parasite)
'general has chain' is the wordplay.
'general' becomes 'lee' (Robert E. Lee - US revolutionary commander).
'has' is a charade indicator (letters next to each other).
'chain' becomes 'ch' (abbreviation for the unit of length).
'lee'+'ch'='LEECH'
'for' acts as a link.
(Other definitions for leech that I've seen before include "Proverbial bloodsucker" , "Old doctor" , "scrounger" , "Blood-sucking worm or parasitical person" , "Clinging type" .)