Gregorian calendar

American  

[gri-gawr-ee-uhn kal-uhn-der] / grɪˈgɔr i ən ˈkæl ən dər /

noun

1. the reformed Julian calendar now in use, according to which the ordinary year consists of 365 days, and a leap year of 366 days occurs in every year whose number is exactly divisible by 4 except centenary years whose numbers are not exactly divisible by 400, such as 1700, 1800, and 1900.

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Gregorian calendar British  

noun

1. the revision of the Julian calendar introduced in 1582 by Pope Gregory XIII and still in force, whereby the ordinary year is made to consist of 365 days and a leap year occurs in every year whose number is divisible by four, except those centenary years, such as 1900, whose numbers are not divisible by 400

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Etymology

Origin of Gregorian calendar

First recorded in 1640–50; named after Pope Gregory XIII; see -ian

Compare meaning

How does gregorian-calendar compare to similar and commonly confused words? Explore the most common comparisons:

• Gregorian calendar vs. Julian calendar

Example Sentences

Each full Moon in a year has a name - a practice that dates back to ancient traditions centuries before the Gregorian calendar existed.

From BBC • Dec. 3, 2025

Foula - which is home to less than 40 people - never fully adopted the modern Gregorian calendar, preferring instead to follow some of the traditions of the Julian calendar.

From BBC • Jan. 12, 2025

The Islamic calendar is a lunar system that adds up to only 354 days and shifts some 11 days from the Gregorian calendar each year—though a single leap day is sometimes added.

From National Geographic • Feb. 26, 2024

The Gregorian calendar, intended to more accurately mark the solar year, was adopted in 1752, adding 11 days.

From Seattle Times • Feb. 17, 2024

On the Gregorian calendar, the one we use today, Newton was born on 4 January 1643, while on the Julian calendar Galileo died right at the end of 1641.

From "The Scientists" by John Gribbin