Lobby leaders of workplace, eagerly expecting novelty dress-up day (9)

I believe the answer is:

halloween

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'day' is the definition.
(Hallowe'en is an example)

'lobby leaders of workplace eagerly expecting novelty' is the wordplay.
'lobby' becomes 'hall' (synonyms).
'leaders' indicates taking the first letters.
The initial letters of 'of workplace eagerly expecting novelty' is 'oween'.
'hall'+'oween'='HALLOWEEN'

'dress-up' acts as a link.
I am not very happy about this link. It may be part of another bit of the clue.

Can you help me to learn more?

(Other definitions for halloween that I've seen before include "Night of October thirty-first" , "Last night in October" , "autumnal celebration" , "Evening of masquerade" , "31st October" .)

I've seen this clue in The Irish Times.

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