Sick, exhausted and badly used (3-5)

I believe the answer is:

ill-spent

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'badly used' is the definition.
The answer and definition are different parts of speech. However, past participle verbs and adjectives occasionally mean the same thing.

'sick exhausted' is the wordplay.
'sick' becomes 'ill' (synonyms).
'exhausted' becomes 'spent' (similar in meaning).
'ill'+'spent'='ILL-SPENT'

'and' acts as a link.

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I've seen this clue in The Irish News.

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