Sloe gin, a volatile, flammable liquid (8)
I believe the answer is:
gasoline
'flammable liquid' is the definition.
The answer and definition can be both substances as well as being singular nouns.
Perhaps there's an association between them I don't understand?
'sloe gin a volatile' is the wordplay.
'volatile' indicates anagramming the letters.
'sloe'+'gin'+'a'='sloegina'
'sloegina' is an anagram of 'GASOLINE'.
Can you help me to learn more?
(Other definitions for gasoline that I've seen before include "US fuel" , "N American petrol" , "US petrol" , "Fossil fuel" , "Sole gain (anag.); petrol" .)