Genuine right to swill ale (4)
I believe the answer is:
real
'genuine' is the definition.
(I know that genuine can be written as real)
'right to swill ale' is the wordplay.
I cannot quite understand how this works, but
'right' could be 'r' (common abbreviation) and 'r' is present in the answer.
an anagram of 'ale' is 'eal' which is within the answer.
No letters remain.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for real that I've seen before include "Actual and tangible" , "---- Madrid, Spanish football club" , "Type of ale" , "Substantial" , "Actual, not imaginary" .)