The story
- Old English · inherited fromrǣdingbōc“a book containing lessons; lectionary”
- Middle English · inherited fromredyng bok
- English todayreading book
From Middle English redyng bok, from Old English rǣdingbōc (“a book containing lessons; lectionary”), equivalent to reading + book.
Etymology from Wiktionary, CC BY-SA 4.0.