Record keeper rubbed out cut by day before feast (6)
I believe the answer is:
sleeve
'record keeper' is the definition.
(I've seen this in another clue)
'by day before feast' is the wordplay.
'by' means one lot of letters go next to another.
'day before' becomes 'eve' (the eve of something is the night before).
'feast' becomes 'sle' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'eve' after 'sle' is 'SLEEVE'.
'rubbed out cut' is the link.
I am not very happy about this link. Some or all of it may be part of another bit of the clue.
Can you help me to learn more?
(Other definitions for sleeve that I've seen before include "Tube" , "Part of clothing covering arm" , "Part of a garment covering the arm" , "with something to hide?" , "It's attached to the armhole" .)