Maintenance of leading medieval tower (6)
I believe the answer is:
upkeep
'maintenance' is the definition.
(I know that maintenance can be written as upkeep)
'leading medieval tower' is the wordplay.
'leading' becomes 'up' (up can mean leading in a game).
'medieval tower' becomes 'keep' (I've seen this before. I am not sure about the 'medieval' bit.).
'up'+'keep'='UPKEEP'
'of' is the link.
Can you help me to learn more?
(Other definitions for upkeep that I've seen before include "Looking after" , "Cost of maintenance, say household" , "Cost of maintaining" , "Cost of support" , "Running costs" .)