- a person who plans.
- a book, similar to a desk calendar, for recording appointments, things to be done, etc.
- a person who makes plans, esp for the development of a town, building, etc
- a chart for recording future appointments, tasks, goals, etc
n.1716, “one who plans,” agent noun from plan (v.). Derogatory variant planster attested from 1945. Meaning “book or device that enables one to plan” is from 1971.