Alcoholic Earl in Clapton only understood by a few people (8)
I believe the answer is:
esoteric
'only understood by a few people' is the definition.
I can't tell whether this definition defines the answer.
'alcoholic earl in clapton' is the wordplay.
'alcoholic' becomes 'sot' (I can't explain this - if you can you should believe this answer much more).
'earl' becomes 'e'.
'in' is an insertion indicator.
'clapton' becomes 'eric' (I've seen this in another clue).
'sot'+'e'='sote'
'sote' inserted inside 'eric' is 'ESOTERIC'.
Can you help me to learn more?
(Other definitions for esoteric that I've seen before include "Secret, private" , "known to a few" , "unintelligible to outsiders" , "Intelligible only to the initiated" , "Mysterious to all but a chosen few" .)