An angler uses it to catch perch (3)

I believe the answer is:

rod

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'perch' is the definition.
(I know that perch can be written as rod)

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

(Other definitions for rod that I've seen before include "Fisherman's item" , "A few yards" , "An angler's stick" , "Bar, shaft" , "pistol" .)

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

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