Notes mostly recall accompanying answer (9)
I believe the answer is:
memoranda
'notes' is the definition.
(more than one memorandum)
'mostly recall accompanying answer' is the wordplay.
'mostly' means to remove the last letter (most but not all of the word).
'recall' becomes 'memory' (I've seen this before).
'accompanying answer' becomes 'anda' (I can't justify this - if you can you should give a lot more credence to this answer).
'memory' with its last letter removed is 'memor'.
'memor'+'anda'='MEMORANDA'
Can you help me to learn more?
(Other definitions for memoranda that I've seen before include "Records" , "Notes recorded for future use" , "Written messages or notes" , "Communications" , "official minutes" .)