But the angler may want to see it sink! (5)
I believe the answer is:
float
'sink' is the definition.
The definition and answer can be both man-made objects as well as being singular nouns.
Maybe you can see an association between them that I can't see?
'but the angler may want to see it' is the wordplay.
I cannot really see how this works, but
'the' could be 't' (the is pronounced as a 't' sound in some dialects) and 't' is located in the answer.
'see' could be 'lo' (archaic exclamation meaning 'look!') and 'lo' is located in the answer.
The remaining letters 'fa' is a valid word which might be clued in a way I don't see.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for float that I've seen before include "What ships do" , "bread supply?" , "Be buoyant" , "Drift aimlessly" , "Put forward (an idea)" .)