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referring to a leap year


noun [countable]

a leap year

bissext also bissextus

noun [countable]

February 29th, the extra day in a leap year

'The Bissextile Beverage – Friday is Feb. 29, a day that doesn't exist three years in four. Rare as it is, the 29th is a fine day for having a celebratory drink … About the last gasp for distinctively bissextile drinks was the '70s. In Washington, a bar called My Mother's Place threw a 1972 Leap Year party featuring Mother's Leap cocktails …'

The Wall Street Journal 23rd February 2008

Contrary to what you might think, bissextile has nothing to do with issues of sexual orientation or gender! It simply refers to a leap year – a year containing February 29th and therefore a total of 366 days. A noun derivative bissext (with a variant bissextus) refers to the extra day itself, though leap day is a common alternative in much wider use. February 29th can also be technically referred to as an intercalary day. Intercalary is an adjective of Latin origin, which describes the insertion of an extra day in the calendar in order to harmonize it with a solar year.

the word bissextile is relatively rare in modern English, but emerges from obscurity every four years

Though bissextile is in fact a very old word, a related noun leapling, used to refer to a person born on February 29th, has only been around since the new millennium. Twenty-first century leaplings, also sometimes known as leapers (or, more affectionately, leapies), can be united through dedicated websites such as leapyearday.com which provide information about special leap day events, list famous births on February 29th, and include an 'honour roll' where leap day babies can submit their names and details.

Related coinages which surface in periodic discussions of the leap day phenomenon include adjective leapless, which is used to describe someone not born on February 29th, noun leapness, for the condition of being born on February 29th, and noun leapship, referring to a relationship between two leaplings.

Background – bissextile

The word bissextile in fact has its origins in the sixteenth century, deriving from the Latin term bissextilis meaning 'having an intercalary day'. In the ancient Roman calendar, the sixth day before the 'Calends of March' (i.e. 24th February, counting back from the beginning of March) occurred twice in a leap year. Hence the term is based on Latin sextus – 'six' – and bis – 'twice' – and means 'twice the sixth day'. The word bissextile is relatively rare in modern English, but emerges from obscurity every four years as illustrated by articles like the one cited above. The phrase année bissextile is however a commonly used French term for leap year.

The term leapling was coined around 2000, combining leap with -ling, a suffix often used to imply that a person or thing is small or very young, as illustrated by words like duckling and seedling. Leapling was initially reserved for the description of new-born leap day babies, with leaper the more general term for a person born on February 29th, but more recent citations show the two used more or less interchangeably.

The use of the word leap in reference to a year with 366 days dates from the time of late Middle English. In years with the extra day, feast days after February came two days rather than one day later than the previous year, and could therefore be said to have 'leaped' a day.

by Kerry Maxwell, author of Brave New Words

This article was first published on 25th February 2008.

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a form of location that involves the underwater detonation of a bomb which causes sound waves that are picked up by ships

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