On which to drink Adam's ale (5)
I believe the answer is:
wagon
'drink adam's ale' is the definition.
Although both the answer and definition are singular nouns, I don't understand how one could define the other.
'on which' is the wordplay.
I cannot really see how this works, but
'on' is within the answer.
The remaining letters 'wag' is a valid word which might be clued in a way I don't see.
This may be the basis of the clue (or it may be nonsense).
'to' acts as a link.
Can you help me to learn more?
(Other definitions for wagon that I've seen before include "Vehicle (on which abstainers travel?)" , "Railway freight vehicle" , "Trailer, railway truck" , "Vehicle for transporting goods" , "Cart; rail truck" .)