Before George at regular intervals (3)
I believe the answer is:
ere
'before' is the definition.
(usually literary)
'george at regular intervals' is the wordplay.
'at regular intervals' indicates alternate letters.
The alternate letters of 'george' are 'ERE'.
(Other definitions for ere that I've seen before include "Old word for before" , "Before (in poetry)" , "Old prior" , "Before (lit.)" , "One who steals" .)