Angler uses it to catch perch (3)

I believe the answer is:

rod

I'm a little stuck... Click here to teach me more about this clue!

'perch' is the definition.
(synonyms)

I cannot understand how the remainder of the clue works.

(Other definitions for rod that I've seen before include "pistol" , "Former measure equal to a quarter of a chain" , "Sceptre" , "Fishing implement" , "The fly fisherman's stick" .)

Want a hint initially instead of a full solution? Install my app