Skilful bottle opener gets into ale (4)
I believe the answer is:
able
'skilful' is the definition.
(I've seen this before)
'bottle opener gets into ale' is the wordplay.
'opener' suggests taking the first letters.
'gets into' is an insertion indicator.
The first letter of 'bottle' is 'b'.
'b' placed inside 'ale' is 'ABLE'.
(Other definitions for able that I've seen before include "... was I ere I saw Elba (palindrome)" , "Having great proficiency or intelligence" , "Practised" , "Adept" , "Competent - sort of seaman" .)