Achilles' aunt in play sees visions (12)
I believe the answer is:
hallucinates
'sees visions' is the definition.
(to hallucinate is to see visions)
'achilles' aunt in play' is the wordplay.
'in play' is an anagram indicator.
'achilles'+'aunt'='achillesaunt'
'achillesaunt' is an anagram of 'HALLUCINATES'.
I've seen this clue in The Guardian.
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