diarist

From diary +‎ -ist.

• IPA^(key): /ˈdaɪəɹɪst/

diarist (plural diarists)

1. One who keeps a diary.
   • 1951 May, R. S. McNaught, “A Veteran Driver's Diary”, in Railway Magazine, page 336:

     Two typical weeks (selected at random and separated by a long interval) are set out in the accompanying tables, and indicate the clear and concise method adopted by the diarist throughout his 42 working years.

• tarsiid