calendar calendar /ˈkæləndɝ/

noun

1. () A list or register of events (appointments or social events or court cases etc)  ( datebook [ N. American] , calendar )
   a list or register of events (appointments or social events or court cases etc)
    I have you on my calendar for next Monday
   I have you on my calendar for next Monday
   
2. () A system of timekeeping that defines the beginning and length and divisions of the year  ( calendar )
   a system of timekeeping that defines the beginning and length and divisions of the year
    She marked her important dates on the calendar hanging in her study.
   She marked her important dates on the calendar hanging in her study.
   
   
3. A tabular array of the days (usually for one year)  ( calendar )
   a tabular array of the days (usually for one year)
   

verb

1. Enter into a calendar  ( calendar )
   enter into a calendar