A bag snatch (4)
I believe the answer is:
grip
This might be a double definition.
'a bag' is the first definition.
(type of travelling bag)
'snatch' is the second definition.
The definition and answer can be both acts as well as being singular nouns.
Perhaps you can see an association between them that I can't see?
Can you help me to learn more?
(Other definitions for grip that I've seen before include "Control" , "Hold hard" , "Deeply affect" , "member of camera crew" , "Secure" .)