Hands on fish back, caught with tail moving (9)
I believe the answer is:
practical
'caught with tail moving' is the definition.
The answer and definition are different parts of speech. However, past participle verbs and adjectives can occasionally mean the same thing.
'hands on fish back' is the wordplay.
'hands' becomes 'tical' (I can't explain this - if you can you should believe this answer much more).
'on' is a charade indicator (letters next to each other).
'fish' becomes 'carp' (carp is a kind of fish).
'back' says the letters should be written in reverse.
'carp' written backwards gives 'prac'.
'tical' after 'prac' is 'PRACTICAL'.
Can you help me to learn more?
(Other definitions for practical that I've seen before include "Concerned with doing rather than with theory" , "Sensible" , "Exam" , "Experiment" , "Down to earth - like Eliot's Cats" .)