Prince and circle not present in penthouse rave (7)
I believe the answer is:
enthuse
'rave' is the definition.
(I've seen this before)
I can't explain the rest of the clue.
(Other definitions for enthuse that I've seen before include "Seen hut? (anag) - show a lively interest" , "Fire" , "Rave" , "Show feeling of eager liking and approval" , "Express eager enjoyment, interest or approval" .)