In ladies' room at parties knocking down spirits? (14)

I believe the answer is:

demoralisation

'knocking down spirits?' is the definition.
(to demoralise someone is to lower their spirits)

'in ladies' room at parties' is the wordplay.
'parties' indicates an anagram (the letters move or party around).
'in'+'ladies'+'room'+'at'='inladiesroomat'
'inladiesroomat' is an anagram of 'DEMORALISATION'.

(Another definition for demoralisation that I've seen is " Discouragement".)

I've seen this clue in The Guardian.

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