Passionate student hugged by a celebrity (6)
I believe the answer is:
aflame
'passionate' is the definition.
(similar in meaning)
'student hugged by a celebrity' is the wordplay.
'student' becomes 'l' (as in L-plates for learner drivers).
'hugged by' means one lot of letters goes inside another (I've seen this in other clues).
'celebrity' becomes 'fame' (celebrity can mean the quality of being famous).
'a'+'fame'='afame'
'l' placed inside 'afame' is 'AFLAME'.
(Other definitions for aflame that I've seen before include "Indicating excitement" , "Ma, flea could be burning" , "On fire" , "Deeply aroused" , "very hot" .)