Office worker at extremely large place of worship (6)
I believe the answer is:
temple
'place of worship' is the definition.
(temple is a kind of place of worship)
'office worker at extremely large' is the wordplay.
'office worker' becomes 'temp' (a temporary office worker).
'at' is a charade indicator (letters next to each other).
'extremely' says to hollow out the word (remove centre letters) (letters on the extremes of the word are used).
'large' with its centre taken out is 'le'.
'temp'+'le'='TEMPLE'
(Other definitions for temple that I've seen before include "London tube station" , "Mormon church" , "Place of worship - side of the head" , "Side of the head or religious building" , "Coy, composed" .)