A survey not repeated (4-4)

I believe the answer is:

once-over

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'a survey' is the definition.
(I have seen 'Quick survey' mean 'once over' so perhaps 'survey' could also mean 'once over')

I don't understand how the rest of the clue works.

Can you help me to learn more?

(Other definitions for once-over that I've seen before include "Rapid inspection" , "Quick examination" , "Quick inspection" , "Cursory examination" , "Quick appraisal" .)

I've seen this clue in The Globe and Mail.

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