a notebook for recording appointments and things to be done, etc.
"She kept her daily schedule organized by writing every meeting and task in her planner before heading out the door."
One who plans.
"The event planner coordinated every detail of the wedding, from the floral arrangements to the guest list."
In plain English: A planner is someone who organizes tasks and schedules to make sure things get done on time.
"She is a good planner who always keeps her calendar packed with appointments."
Usage: A planner is a person or organization that creates detailed schedules or strategies to organize future events. Use this term when referring to someone responsible for coordinating logistics rather than the physical notebook used for writing down tasks.
The word planner is formed by adding the suffix "-er" to the verb "plan." It entered English as a straightforward agent noun meaning one who makes plans.