Seaman overhauled Polaris after power cut (6)

I believe the answer is:

sailor

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

I don't understand the rest of the clue.

(Other definitions for sailor that I've seen before include "10 [MARINER]" , "Tar, AB" , "Sinbad, for example" , "Seafarer" , "One in the main" .)

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