Cheap fish? (5)

I believe the answer is:

skate

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'fish?' is the definition.
(skate is a kind of fish)

I can't explain the rest of the clue.

(Other definitions for skate that I've seen before include "Fish; go on ice" , "Runner" , "move around ice" , "Food fish" , "Ice-gliding blade; fish" .)

I've seen this clue in the Evening Standard.

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