Occupation includes garden terrace (5)
I believe the answer is:
patio
'garden terrace' is the definition.
(I've seen this before)
'occupation includes' is the wordplay.
'includes' indicates a hidden word.
'PATIO' is hidden within 'occupation'.
(Other definitions for patio that I've seen before include "Paved area alongside a house" , "Paved area beside house, often in back garden" , "Barbecue location?" , "Spanish courtyard" , "Hard surface" .)