Crossword Genius

Horse getting old on drink (5)

Ross

I believe the answer is:

pinto

'horse' is the definition.
(pinto is a kind of horse)

'old on drink' is the wordplay.
'old' becomes 'o' (common abbreviation eg in OE for Old English).
'on' is a charade indicator (letters next to each other).
'drink' becomes 'pint' (I've seen this before**).
'o' after 'pint' is 'PINTO'.

'getting' is the link.

(Other definitions for pinto that I've seen before include "A piebald pony" , "Mount" , "Piebald horse (US)" , "patchy horse" , "H [HORSE]" .)

I've seen this clue in The Independent.
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