The catalogue’s in the dining-room (5)
I believe the answer is:
table
'the catalogue's' is the definition.
(thesaurus)
'the dining-room' is the wordplay.
'the' becomes 't' (the is pronounced as a 't' sound in some dialects).
'dining-room' becomes 'able' (I can't justify this - if you can you should give a lot more credence to this answer).
't'+'able'='TABLE'
'in' acts as a link.
Can you help me to learn more?
(Other definitions for table that I've seen before include "League --; multiplication --" , "Board; data list" , "Food; flat gem surface" , "Put forward for formal discussion" , "Food put on this" .)