Horse takes drink going to the front, going on and on (7)
I believe the answer is:
nagging
'on' is the definition.
Both the definition and answer are adjectives. Perhaps they are linked in a way I don't understand?
'horse takes drink going to the front going on' is the wordplay.
'horse' becomes 'nag' (term for an old horse).
'takes drink' becomes 'gin' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'to the front' suggests taking the first letters.
'going on' is a charade indicator (letters next to each other).
The first letter of 'going' is 'g'.
'nag'+'gin'+'g'='NAGGING'
'and' acts as a link.
Can you help me to learn more?
(Other definitions for nagging that I've seen before include "Carping" , "Pestering, plaguing" , "Continually complaining or faultfinding" , "Henpecking" , "Persistent (pain)" .)