Don perhaps has well to drain off (8)
I believe the answer is:
spaniard
'don perhaps' is the definition.
The answer and definition can be both people as well as being singular nouns.
Maybe they are linked in a way I don't understand?
'well to drain off' is the wordplay.
'well' becomes 'spa' (both can mean a spring or water source).
'to' is a charade indicator (letters next to each other).
'off' is an anagram indicator.
'drain' anagrammed gives 'niard'.
'spa'+'niard'='SPANIARD'
'has' is the link.
Can you help me to learn more?
(Other definitions for spaniard that I've seen before include "Type mostly found in Madrid" , "Slope-measuring instrument" , "European national" , "A native of Iberian country" , "Nadal perhaps" .)