perpetual calendar

noun

: a table for finding the day of the week for any one of a wide range of dates

Examples of perpetual calendar in a Sentence

Recent Examples on the Web

The movement, with an 80-hour power reserve and a frequency of 4 Hz, is also home to a perpetual calendar and an equation of time display, showing the difference between mean solar time, shown on the main dial, and true solar time, which fluctuates due to the Earth’s elliptical orbit. — Nicole Hoey, Robb Report, 26 June 2026

The extended reserve is crucial for perpetual calendars, which are notoriously difficult to reset. — Carol Besler, Forbes.com, 16 June 2026

This is the first perpetual calendar whose displays and its moon phase can be adjusted both forward and backward through a single crown position. — Fairchild Studio, Footwear News, 16 Apr. 2026

According to Ben-Yehuda, the industry threshold for intricacy is the perpetual calendar, a constellation of sub-dials tracking day, month, year (even leap years) and sometimes moon phase. — Adam Erace, Fortune, 4 Apr. 2026

Word History

First Known Use

1577, in the meaning defined above

Rhymes for perpetual calendar

• calender
• kalendar