Unrestrained, Wooster almost enters row (9)
I believe the answer is:
libertine
'unrestrained' is the definition.
Both the definition and answer are adjectives. Maybe there's a link between them I don't understand?
'wooster almost enters row' is the wordplay.
'wooster almost' becomes 'berti' (I am not sure about this - if you are sure you should believe this answer much more).
'enters' means one lot of letters goes inside another.
'row' becomes 'line' (as in a row of things).
'berti' inserted inside 'line' is 'LIBERTINE'.
Can you help me to learn more?
(Other definitions for libertine that I've seen before include "Lustful" , "Debauchee" , "Say, Don Giovanni" , "Rou" , "Roue" .)