Rude to a silly patriot (8)
I believe the answer is:
loyalist
'patriot' is the definition.
(I've seen this before)
'rude to a silly' is the wordplay.
'rude' indicates an anagram.
'to'+'a'+'silly'='toasilly'
'toasilly' with letters rearranged gives 'LOYALIST'.
(Other definitions for loyalist that I've seen before include "supporter of British rule?" , "One true to monarch or government" , "One supporting established government" , "One staying in support of a ruler or government" , "Patriot" .)