Heavy female companion supported by staff (8)
I believe the answer is:
henchman
'heavy' is the definition.
(thesaurus)
'female companion supported by staff' is the wordplay.
'female' becomes 'hen' (female chicken).
'companion' becomes 'ch' (Companion of Honour).
'supported by' says to put letters next to each other (in a down clue, some letters hold up others).
'staff' becomes 'man' (as in staffing or manning a particular place).
'hen'+'ch'+'man'='HENCHMAN'
(Other definitions for henchman that I've seen before include "Faithful attendant" , "Collaborator, sidekick" , "Right-hand man" , "abettor in crime?" , "trusty supporter" .)