State of perfect happiness (7)
I believe the answer is:
nirvana
'state of perfect happiness' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for nirvana that I've seen before include "State of perfect happiness" , "Eastern place of complete bliss" , "Ultimate tranquil state" , "'Transcendent state, the final goal of Buddhism (7)'" , "Iran van (anag) - blissful state!" .)