Skinny Australian suppresses most of light gas after reduction (9)
I believe the answer is:
cutaneous
'skinny' is the definition.
(I've seen this before)
'australian suppresses most of light gas after reduction' is the wordplay.
'australian' becomes 'aus' (common abbreviation).
'suppresses' is an insertion indicator.
'most of light gas' becomes 'neo' (I am not sure about this - if you are sure you should believe this answer much more).
'after' is a charade indicator (letters next to each other).
'reduction' becomes 'cut' (cut is a kind of reduction).
'aus' placed around 'neo' is 'aneous'.
'aneous' after 'cut' is 'CUTANEOUS'.
Can you help me to learn more?
(Other definitions for cutaneous that I've seen before include "Relating to the skin" , "Skinny" .)