Dipper — another constellation wheeling around us (5)

I believe the answer is:

ousel

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'dipper' is the definition.
(I've seen this before)

I cannot understand how the remainder of the clue works.

(Other definitions for ousel that I've seen before include "Winger" , "Feathered vertebrate" , "Othello?" , "Flyer" , "Strange louse for a blackbird" .)

I've seen this clue in The Times and The Sunday Times.

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