Son chortling, making a killing (9)
I believe the answer is:
slaughter
'a killing' is the definition.
(I know that slaughter is a type of killing)
'son chortling' is the wordplay.
I cannot really see how this works, but
'son' could be 's' (genealogical abbreviation for son) and 's' is found in the answer.
The remaining letters 'laughter' is a valid word which might be clued in a way I don't see.
This explanation may well be incorrect...
'making' acts as a link.
Can you help me to learn more?
(Other definitions for slaughter that I've seen before include "Kill (animals) for food" , "Murder" , "Massacre" , "Wholesale killing" , "Widespread killing" .)