A common fund for Catherine (5)
I believe the answer is:
kitty
This might be a double definition.
'a common fund' is the first definition.
'kitty' can be an answer for 'fund' (I've seen this before). I am unsure of the 'a common' bit.
'catherine' is the second definition.
(Kitty can be short for Catherine)
'for' acts as a link.
Can you help me to learn more?
(Other definitions for kitty that I've seen before include "Communal funds" , "Communal fund" , "Pool of money - how Anne Frank addressed her diary" , "Pool - puss" , "Pool - cat" .)