Force restraint of member: not right (6)
I believe the answer is:
legion
'force' is the definition.
(legion is a kind of force)
'restraint of member not right' is the wordplay.
'restraint of member' becomes 'leg-iron' (restraint for someone's leg).
'not' indicates named letters should be taken away.
'right' becomes 'r' (common abbreviation).
'legiron' with 'r' taken away is 'LEGION'.
(Other definitions for legion that I've seen before include "The French have a Foreign one" , "Large unit of the old Roman army" , "Roman military formation" , "Part of an army; many" , "Military unit of ancient Rome" .)