More efficient one listed? (6)
I believe the answer is:
leaner
'more efficient' is the definition.
(I've seen this in another clue)
'one listed?' is the wordplay.
I cannot quite see how this works, but
'one' could be 'ane' (synonyms) and 'ane' is found in the answer.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for leaner that I've seen before include "One with an inclination" , "Thinner, with less fat" , "less corpulent?" , "less bulky" , "less productive" .)