Acid drops? (6,5)

I believe the answer is:

bitter tears

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'acid drops?' is the definition.
I know nothing about this answer so I cannot judge whether this works.

'acid drops?' is the wordplay.
'acid' becomes 'bitter' (synonyms).
'drops?' becomes 'tears' (I've seen this before).
'bitter'+'tears'='BITTER TEARS'

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I've seen this clue in the Evening Standard.

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