Jan

Units & Measurements abbreviation · Month

Jan
Stands forJanuary
CategoriesUnits & Measurements

Jan stands for January, a month abbreviation.

The first month of the Gregorian calendar, with 31 days. It is named after Janus, the two-faced Roman god of doorways and beginnings, who looks back at the old year and forward to the new.

Example: Rent is due Jan. 1, and the lease renews on Jan. 31.

Usage notes

AP style abbreviates January as Jan. with a period when it appears with a specific date (Jan. 15, 2027) but spells it out alone or with only a year (January 2027). Roman consuls began taking office on January 1 from 153 BC, which helped make it the start of the civil year, though England kept March 25 as New Year's Day until 1752. January's birthstone is garnet.

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