- A personal record of occurrences, experiences, and reflections kept on a regular basis; a diary.
- An official record of daily proceedings, as of a legislative body.
- Nautical A ship's log.
- Accounting A daybook.
- Accounting A book of original entry in a double-entry system, listing all transactions and indicating the accounts to which they belong.
- A newspaper.
- A periodical presenting articles on a particular subject: a medical journal.
- The part of a machine shaft or axle supported by a bearing.