Measure of land sacred at the centre (4)
I believe the answer is:
acre
'measure of land' is the definition.
(I've seen this in another clue)
'sacred at the centre' is the wordplay.
'at the centre' indicates the central letters.
The central letters of 'sacred' are 'ACRE'.
(Other definitions for acre that I've seen before include "Unit of area of 4,840 square yards" , "Imperial land measurement" , "marine location in Israel" , "A state of W Brazil" , "Square measure of land" .)