Some soldiers making racket, thanks to cat (9)
I believe the answer is:
battalion
'some soldiers' is the definition.
(I've seen this before)
'making racket thanks to cat' is the wordplay.
'making racket' becomes 'bat' (I can't justify this - if you can you should give a lot more credence to this answer).
'thanks' becomes 'ta' (UK informal version of 'thank you').
'to cat' becomes 'lion' (lion is a kind of cat).
'bat'+'ta'+'lion'='BATTALION'
Can you help me to learn more?
(Other definitions for battalion that I've seen before include "infantry unit" , "army group" , "Body of soldiers" , "Army unit" , "many troops" .)