One French landing around lines out of balance (9)
I believe the answer is:
unequally
'out of balance' is the definition.
Both the definition and answer are adverbs. Maybe you can see a link between them that I can't see?
'one french landing around lines' is the wordplay.
'one french' becomes 'une' ('one' in French).
'landing' becomes 'quay' (quay is a kind of landing).
'around' is an insertion indicator.
'lines' becomes 'll' (an abbreviation for line written twice).
'quay' going around 'll' is 'qually'.
'une'+'qually'='UNEQUALLY'
Can you help me to learn more?
(Other definitions for unequally that I've seen before include "Not in identical, fair, way" , "in unbalanced way" , "In an uneven manner" .)