Device that decreases new purser's store?

I believe the answer is:

trouserpress

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'device that decreases' is the definition.
The definition suggests a singular noun which matches the answer.

'new purser's store?' is the wordplay.
'new' indicates anagramming the letters.
'pursers'+'store'='pursersstore'
'pursersstore' anagrammed gives 'TROUSER PRESS'.

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(Another definition for trouserpress that I've seen is " may be found in hotel room".)

I've seen this clue in The Daily Mail.

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