Addresses held at this large relocating centre (7)
I believe the answer is:
lectern
'addresses held at this large relocating centre' is the definition.
The definition suggests a singular noun which matches the answer.
'at this large relocating centre' is the wordplay.
'at' means one lot of letters go next to another.
'this large' becomes 'L' (eg in clothes sizes).
'relocating' indicates an anagram (I've seen 'relocated' mean this).
'centre' with letters rearranged gives 'ectern'.
'l' next to 'ectern' is 'LECTERN'.
Can you help me to learn more?
(Other definitions for lectern that I've seen before include "Bible stand" , "Desk for a standing reader" , "Church reading desk" , "Stand with sloping top to hold book" , "stand in church" .)