Paraffin oil reek — nose is perturbed (8)
I believe the answer is:
kerosene
'paraffin oil' is the definition.
(I've seen this before)
'reek nose is perturbed' is the wordplay.
'is perturbed' is an anagram indicator.
'reek'+'nose'='reeknose'
'reeknose' with letters rearranged gives 'KEROSENE'.
(Other definitions for kerosene that I've seen before include "No seeker for American fuel oil" , "Paraffin oil (E, not I)" , "Combustible" , "Sore knee (anag.)" , "Oil used as fuel in lamps and heaters" .)