n. pl. di·a·ries 1. a. A usually daily written record of personal experiences and observations; a journal. b. A daily record of events or measurable phenomena, usually kept to track patterns over time: kept a diary of blood sugar levels. 2. A book or computer file used for keeping such a record. [Latin diārium, daily allowance, daily journal, from diēs, day; see dyeu- in the Appendix of Indo-European roots.] |
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