Main tower of castle (4)
I believe the answer is:
keep
(Other definitions for keep that I've seen before include "Main tower within the walls of a castle" , "Retain; strong tower" , "Retain or care for" , "Guard" , "run" .)
I believe the answer is:
keep
(Other definitions for keep that I've seen before include "Main tower within the walls of a castle" , "Retain; strong tower" , "Retain or care for" , "Guard" , "run" .)