Something used by angler for river fish? (4)

I believe the answer is:
reel
'something used by angler' is the definition.
I can't judge whether this definition defines the answer.
'river fish?' is the wordplay.
'river' becomes 'r' (abbreviation).
'fish?' becomes 'eel' (eel is a type of fish).
'r'+'eel'='REEL'
'for' acts as a link.
Can you help me to learn more?
(Other definitions for reel that I've seen before include "long stretch of film" , "Dance; winding cylinder" , "The angler pulls in his line using this" , "Part of a film; stagger" , "Film spool" .)
