Unemployed barmaid learned to some extent (4)
I believe the answer is:
idle
'unemployed' is the definition.
(similar in meaning)
'barmaid learned to some extent' is the wordplay.
'to some extent' indicates the answer is hidden within the clue.
'IDLE' is hidden within 'barmaid learned'.
(Other definitions for idle that I've seen before include "without basis" , "Not in action or at work" , "lndolent" , "Monty Python's Eric, b. 1943" , "goalless" .)