Waste away after collecting a prize (7)

I believe the answer is:

atrophy

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'waste away after collecting' is the definition.
'atrophy' can be an answer for 'waste' (atrophy means to waste away). I'm not certain of the 'away after collecting' bit.

'a prize' is the wordplay.
'prize' becomes 'trophy' (synonyms).
'a'+'trophy'='ATROPHY'

Can you help me to learn more?

(Other definitions for atrophy that I've seen before include "Waste away as through lack of food" , "Decay" , "Decline" , "shrivel" , "Degeneration" .)

I've seen this clue in The Irish News.

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