calendar
Definition
a system for organizing days for social, religious, commercial, or administrative purposes; a chart or notebook showing the days, weeks, and months of a year.
Español Un sistema para organizar días con propósitos sociales, religiosos, comerciales o administrativos; un gráfico o cuaderno que muestra los días, semanas y meses del año.
Example
"I marked the meeting date on my calendar to make sure I wouldn't forget."