Be upset with semi-meltdown – it means someone's gutted (14)

I believe the answer is:

disembowelment

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'it means someone's gutted' is the definition.
The definition suggests a singular noun which matches the answer.

'be upset with semi-meltdown' is the wordplay.
'upset with' is an anagram indicator.
'semi'+'meltdown'='semimeltdown'
'be' with its letters anagrammed with 'semimeltdown' makes 'DISEMBOWELMENT'.

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I've seen this clue in The Guardian.

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