Household of soldiers, mature (6)
I believe the answer is:
menage
'household' is the definition.
('menage' can be a synonym of 'household')
'soldiers mature' is the wordplay.
'soldiers' becomes 'men' (I've seen this before).
'mature' becomes 'age' ('age' can be a synonym of 'mature').
'men'+'age'='MENAGE'
'of' is the link.
(Other definitions for menage that I've seen before include "Social unit living together" , "live together" , "Members of a household" , "Persons of household" , "A household, sometimes naughtily a trois" .)