It's fanciful to work with hothead on Islamic adaptation (9)
I believe the answer is:
whimsical
'it's fanciful' is the definition.
(I've seen this before)
'work with hothead on islamic adaptation' is the wordplay.
'work' becomes 'w' (physics abbreviation).
'with' is a charade indicator (letters next to each other).
'hothead' becomes 'h' (head letter of 'hot').
'on' says to put letters next to each other.
'adaptation' indicates an anagram.
'islamic' anagrammed gives 'imsical'.
'w'+'h'+'imsical'='WHIMSICAL'
'to' acts as a link.
(Other definitions for whimsical that I've seen before include "Delicately playful" , "Fanciful, fantastical" , "Playfully quaint" , "Fanciful or playful" , "Appealingly fanciful" .)