Serving a meat. I abandoned ... this? (13)

I believe the answer is:

vegetarianism

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'this?' is the definition.
The definition suggests a singular noun which matches the answer.

'serving a meat i abandoned' is the wordplay.
'abandoned' indicates an anagram (the original order is abandoned).
'serving'+'a'+'meat'+'i'='servingameati'
'servingameati' with letters rearranged gives 'VEGETARIANISM'.

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I've seen this clue in The Telegraph.

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