Render defenceless with Garda's gun (6)
I believe the answer is:
disarm
'render defenceless' is the definition.
(I've seen this before)
'with garda's gun' is the wordplay.
'with' is a charade indicator (letters next to each other).
'garda's' becomes 'dis' (I can't explain this - if you can you should give a lot more credence to this answer).
'gun' becomes 'arm' (I've seen this in other clues).
'dis'+'arm' is 'DISARM'.
Can you help me to learn more?
(Other definitions for disarm that I've seen before include "Abandon MAD" , "Relieve of weapons" , "Placate" , "Give up weapons" , "Render harmless" .)