Barbecue site (5)
'barbecue site' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for patio that I've seen before include "area near house" , "Place to sit" , "Exterior paved area" , "Paved outdoor area" , "Inner courtyard" .)
(Other definitions for backyard that I've seen before include "area behind building" , "Ground behind my own house - not where I want development?" .)