Cut down thrones (7)
I believe the answer is:
shorten
'cut down' is the definition.
(shortening is a kind of cutting down)
'thrones' is the wordplay.
'thrones' anagrams to 'SHORTEN'.
However, I'm not clear how this is indicated.
Can you help me to learn more?
(Other definitions for shorten that I've seen before include "Truncate" , "Curtail" , "Cut back" , "Prune" , "Put extra fat" .)