Huge reduction in fuel that's mined (8)
I believe the answer is:
colossal
'mined' is the definition.
Both the answer and definition are adjectives. Maybe they are linked in a way I don't understand?
'huge reduction in fuel' is the wordplay.
'huge reduction' becomes 'loss' (I've seen this in other clues. I am not sure about the 'huge' bit.**).
'in' means one lot of letters goes inside another.
'fuel' becomes 'coal' (coal is a kind of fuel).
'loss' put into 'coal' is 'COLOSSAL'.
'that's' is the link.
Can you help me to learn more?
(Other definitions for colossal that I've seen before include "Stupendous" , "Giant" , "Huge, vast" , "Jumbo" , "Mammoth" .)