Pedant and stoic clash explosively (10)
I believe the answer is:
scholastic
'pedant' is the definition.
(I know that pedant can be written as scholastic)
'stoic clash explosively' is the wordplay.
'explosively' indicates anagramming the letters.
'stoic'+'clash'='stoicclash'
'stoicclash' is an anagram of 'SCHOLASTIC'.
'and' acts as a link.
(Other definitions for scholastic that I've seen before include "Relating to education" , "Pertaining to teaching and educational establishments" , "Academic" , "Learned" , "Educative" .)