Petrol (4)
(Other definitions for fuel that I've seen before include "Gas, oil or petrol, for instance" , "Substance to produce energy" , "Stuff to burn" , "Burned source of energy" , "Eg, coal or petrol" .)
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">petrol</span>' is the definition.<br/ ><span class="explanation-format__explanation">(synonyms)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for gas that I've seen before include "Oxygen maybe" , "Something exciting" , "Talk idly; fuel" , "Talk profusely" , "Eg, nitrogen" .)