Drink down in the centre field (6)
I believe the answer is:
meadow
'field' is the definition.
(a meadow is a field)
'drink down in the centre' is the wordplay.
'drink' becomes 'mead' (mead is a kind of drink).
'in the centre' means to look at the middle letters.
The central letters of 'down' are 'ow'.
'mead'+'ow'='MEADOW'
(Other definitions for meadow that I've seen before include "Pasture" , "A field of lush grass" , "Piece of grassland" , "A field of rich grass" , "Paddock" .)