Teased or deceived some poor fish (6)
I believe the answer is:
codded
This clue could be a double definition.
'teased' is the first definition.
('cod' can be a synonym of 'tease')
'deceived some poor fish' is the second definition.
'codded' can be an answer for 'deceived' (codding is a kind of deceiving). I am not certain of the 'some poor fish' bit.
'or' is the link.
Can you help me to learn more?
(Other definitions for codded that I've seen before include "Deceived like popular fish" , "Fooled, duped" , "Informally fooled-sounds fishy" , "Hoaxed with large sea-fish?" .)