Two books, each absorbing day after day (4)
I believe the answer is:
edda
'two books' is the definition.
'edda' can be an answer for 'books' (I've seen this before). I'm unsure of the 'two' bit.
'each absorbing day after day' is the wordplay.
'each' becomes 'ea' (abbreviation).
'absorbing' means one lot of letters goes inside another.
'day after day' becomes 'DD' (two abbreviations for day).
'ea' placed around 'dd' is 'EDDA'.
Can you help me to learn more?
(Other definitions for edda that I've seen before include "series of stories" , "Book of Icelandic poetry" , "Old tales" , "One of the two old Icelandic poetic books" , "Scandinavian books of myths" .)