Long live the Emperor of Zanzibar, unclothed and dancing (6)

I believe the answer is:

banzai

'long live the emperor' is the definition.
(Japanese phrase used to celebrate the emperor)

I cannot understand how the rest of the clue works.

(Other definitions for banzai that I've seen before include "Traditional Japanese battle cry" , "bringing outcry in Japan" , "Japanese battle cry or cheer" .)

I've seen this clue in The Guardian.

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