Toss cats aside (4)
I believe the answer is:
cast
'toss cats aside' is the definition.
'cast' can be an answer for 'toss' (I've seen this in another clue). I'm unsure of the 'cats aside' bit.
'toss cats' is the wordplay.
'toss' is an anagram indicator.
'cats' is an anagram of 'CAST'.
Can you help me to learn more?
(Other definitions for cast that I've seen before include "Throw out line for fish" , "characters together" , "Discard; mould" , "'Send forth, a spell perhaps (4)'" , "In which player" .)