Rustic is also part crazy (8)
I believe the answer is:
pastoral
'rustic' is the definition.
('pastoral' can be a synonym of 'rustic')
'also part crazy' is the wordplay.
'crazy' is an anagram indicator.
'also'+'part'='alsopart'
'alsopart' anagrammed gives 'PASTORAL'.
'is' is the link.
(Other definitions for pastoral that I've seen before include "Bucolic, rural" , "To do with shepherds, or concerned with spiritual guidance" , "bishop's staff" , "Country's" , "of minister's duties" .)