Women must have a way with liquid fuel being uneconomical (8)
I believe the answer is:
wasteful
'uneconomical' is the definition.
('wasteful' can be a synonym of 'uneconomical')
'women must have a way with liquid fuel' is the wordplay.
'women' becomes 'w'.
'must have' says to put letters next to each other.
'way' becomes 'st' (**).
'with' says to put letters next to each other.
'liquid' indicates an anagram.
'fuel' is an anagram of 'eful'.
'w'+'a'+'st'+'eful'='WASTEFUL'
'being' is the link.
(Other definitions for wasteful that I've seen before include "Uneconomical" , "Faults we consider being profligate" , "spendthrift" , "Prodigal" , "Extravagant" .)