Ace lawyer required by heroin-taking group (3,4)
I believe the answer is:
dab hand
'ace' is the definition.
Both the definition and answer are singular nouns.
Maybe there's an association between them I don't understand?
'lawyer required by heroin-taking group' is the wordplay.
I cannot really understand how this works, but
'lawyer' could be 'da' (abbreviation for District Attorney) and 'da' is found within the answer.
'heroin' could be 'h' (synonyms) and 'h' is found in the answer.
'group' could be 'band' (band can mean a group of people) and 'band' is found in the remaining letters.
No letters remain.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for dab hand that I've seen before include "An informal expert such as band had" , "Barely wash" , "Past master" , "cursory wash?" .)