Dress at home (7)
![Ross](/clue/static/ross-mug.min.png)
I believe the answer is:
habitat
'home' is the definition.
(thesaurus)
'dress at' is the wordplay.
'dress' becomes 'habit' (habit is a kind of dress**).
'habit'+'at'='HABITAT'
(Other definitions for habitat that I've seen before include "Domain" , "Usual abode" , "Home ground of an animal" , "place haunted" , "Local environment" .)