Supporter of monarchy (8)
![Ross](/clue/static/ross-mug.min.png)
I believe the answer is:
royalist
'supporter of monarchy' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for royalist that I've seen before include "Monarch's supporter" , "Civil War participant" , "Monarchist" , "one in civil war" , "rightwinger?" .)