daybook/ˈdeɪˌbʊk/daybook means A daily chronicle; a diary. Lexicurio rates it Rare gem — a strength score of 84 out of 100.daybook is pronounced /ˈdeɪˌbʊk/.EtymologyFrom day + book. First attested in 1571. Cognate with Dutch dagboek (“diary, journal, logbook”), German Tagebuch (“diary, journal, daybook”), Danish dagbog (“diary”), Swedish dagbok (“diary, logbook, journal, daybook”).nounA daily chronicle; a diary.“It was a working document, a sort of lab notebook, and since I have called it a daybook, it has become the most valuable resource I have It takes me about six weeks to fill a daybook, and when I'm finished with one I go back through it and pick out anything that I need to work on in the next book.”An accounting journal.“Since these memoranda were marked down from day to day and the entries followed one another day by day, this first book of accounts was called a "daybook."”A logbook.