Scene of some pierrot shows (4)

I believe the answer is:

pier

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But I can't explain it at all! Could you help me understand?

(Other definitions for pier that I've seen before include "Ripe as a jetty (4)" , "Landing-stage or promenade" , "Support for two adjacent bridge spans" , "Seaside structure" , "Platform built out from the shore, supported on piles" .)

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