Creature in minor gas explosion? (8)
I believe the answer is:
organism
'creature' is the definition.
(thesaurus)
'minor gas explosion?' is the wordplay.
'explosion?' indicates anagramming the letters (I've seen 'explosion' mean this).
'minor'+'gas'='minorgas'
'minorgas' anagrammed gives 'ORGANISM'.
'in' acts as a link.
(Other definitions for organism that I've seen before include "individual creation" , "Living animal or plant" , "Any living entity" , "Living thing -- man's giro (anag)" , "Body - cell - Mao grins (anag)" .)