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bissextile

American  
[bahy-seks-til, -tahyl, bih-] / baɪˈsɛks tɪl, -taɪl, bɪ- /

adjective

  1. containing or noting the extra day of leap year.

    The years 1980 and 1984 were both bissextile.


noun

  1. leap year.

bissextile British  
/ bɪˈsɛkstaɪl /

adjective

  1. (of a month or year) containing the extra day of a leap year

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

noun

  1. a rare name for leap year

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of bissextile

1585–95; < Late Latin bi ( s ) sextilis ( annus ) leap year, equivalent to bissext ( us ) bissextus + -ilis -ile

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Hence, it is necessary to suppress the bissextile day at the end of every century which is not divisible by 400, while it is retained at the end of those which are divisible by 400.

From Project Gutenberg

For, on account of our intercalation of one day every bissextile year, the Mexican year receded, as compared with ours, one day every four years.

From Project Gutenberg

Tescoco. 1st year of Mexican Cycle  1 Tochtli 1454 Dec. 31 Dec. 21 Jan. 9 Dec. 30   Bissextile year  3 Tecpatl 1456 30 20 8 29     do.

From Project Gutenberg

Nevertheless, as all this was not enough, because the Year consists of 365 Days, 6 Hours, wanting about 11 Minutes, the Emperor would have every 4 Years, a Year of 366 Days, which additional Day should be plac'd between the 6th and 7th of the Calends of March, so that there were two 6th Days of the Calends of March, in such a Year, which was therefore call'd Bissextile, because the 6th Day was reckon'd twice before they proceeded to the next.

From Project Gutenberg

I am oblig'd to M. Du Puis, said La Foret, for having started this Subject of Conversation; for I had been a long time desirous to know what was meant by the Bissextile Year, by Old and New Style, and what was the real Cause of all those Alterations.

From Project Gutenberg