Connections for a cat, by the sound of it (5)
I believe the answer is:
links
'connections' is the definition.
(I know this)
'cat by the sound of it' is the wordplay.
'cat' becomes 'lynx' (lynx is a kind of cat).
'by the sound of it' indicates a 'sounds like' (homophone) clue.
'lynx' is a homophone of 'LINKS'.
'for a' is the link.
(Other definitions for links that I've seen before include "Bonds" , "Seaside golf course - parts of a chain" , "Connecting parts" , "provides connections to other websites" , "Joins on the golf course?" .)