Owner backing company trophy by worker (8)
I believe the answer is:
occupant
'owner' is the definition.
(thesaurus)
'backing company trophy by worker' is the wordplay.
'backing' says the letters should be written in reverse.
'company' becomes 'co' (abbreviation).
'trophy' becomes 'cup' (cup is a kind of trophy).
'by' says to put letters next to each other.
'worker' becomes 'ant' (worker is a type of ant).
'co' backwards is 'oc'.
'oc'+'cup'+'ant'='OCCUPANT'
(Other definitions for occupant that I've seen before include "Inhabitant, resident" , "One holding position or residing in house" , "Insider" , "Tenant - resident" , "Holder of a position or office" .)