A fortnight is a unit of time equal to 14

day A day is the time period of a full rotation of the Earth with respect to the Sun. On average, this is 24 hours, 1440 minutes, or 86,400 seconds. In everyday life, the word "day" often refers to a solar day, which is the length between two ...

s (two

week A week is a unit of time equal to seven days. It is the standard time period used for short cycles of days in most parts of the world. The days are often used to indicate common work days and rest days, as well as days of worship. Weeks are of ...

s). The word derives from the

Old English Old English (, ), or Anglo-Saxon, is the earliest recorded form of the English language, spoken in England and southern and eastern Scotland in the early Middle Ages. It was brought to Great Britain by Anglo-Saxon settlers in the mid-5th ...

term , meaning "" (or "fourteen days," since the Anglo-Saxons counted by nights).

Astronomy and tides

astronomy Astronomy () is a natural science that studies celestial objects and phenomena. It uses mathematics, physics, and chemistry in order to explain their origin and evolution. Objects of interest include planets, moons, stars, nebulae, g ...

, a ''lunar fortnight'' is half a lunar synodic month, which is equivalent to the

mean There are several kinds of mean in mathematics, especially in statistics. Each mean serves to summarize a given group of data, often to better understand the overall value ( magnitude and sign) of a given data set. For a data set, the '' ar ...

period between a full moon and a new moon (and vice versa). This is equal to 14.77 days. It gives rise to a lunar fortnightly tidal constituent (see: Long-period tides).

Analogs in other languages

In many languages, there is no single word for a two-week period, and the equivalent terms "two weeks", "14 days", or "15 days" ( counting inclusively) have to be used. *

Celtic languages The Celtic languages (usually , but sometimes ) are a group of related languages descended from Proto-Celtic. They form a branch of the Indo-European language family. The term "Celtic" was first used to describe this language group by Edward ...

: in

Welsh Welsh may refer to: Related to Wales * Welsh, referring or related to Wales * Welsh language, a Brittonic Celtic language spoken in Wales * Welsh people People * Welsh (surname) * Sometimes used as a synonym for the ancient Britons (Celtic peopl ...

, the term ''pythefnos'', meaning "15 nights", is used. This is in keeping with the Welsh term for a week, which is ''wythnos'' ("eight nights"). In Irish, the term is ''coicís''. * Similarly, in

Greek Greek may refer to: Greece Anything of, from, or related to Greece, a country in Southern Europe: *Greeks, an ethnic group. *Greek language, a branch of the Indo-European language family. **Proto-Greek language, the assumed last common ancestor ...

, the term δεκαπενθήμερο (''dekapenthímero''), meaning "15 days", is used. * The

Hindu calendar The Hindu calendar, Panchanga () or Panjika is one of various lunisolar calendars that are traditionally used in the Indian subcontinent and Southeast Asia, with further regional variations for social and Hindu religious purposes. They adopt ...

uses the

Sanskrit Sanskrit (; attributively , ; nominally , , ) is a classical language belonging to the Indo-Aryan languages, Indo-Aryan branch of the Indo-European languages. It arose in South Asia after its predecessor languages had Trans-cultural diffusion ...

word पक्ष "pakṣa", meaning one half of a

lunar month In lunar calendars, a lunar month is the time between two successive syzygies of the same type: new moons or full moons. The precise definition varies, especially for the beginning of the month. Variations In Shona, Middle Eastern, and Eur ...

, which is between 14 and 15 solar days. * In

Romance languages The Romance languages, sometimes referred to as Latin languages or Neo-Latin languages, are the various modern languages that evolved from Vulgar Latin. They are the only extant subgroup of the Italic languages in the Indo-European language ...

there are the terms ''quincena'' (or ''quince días'') in Galician and Spanish, ''quinzena'' or ''quinze dies'' in

Catalan Catalan may refer to: Catalonia From, or related to Catalonia: * Catalan language, a Romance language * Catalans, an ethnic group formed by the people from, or with origins in, Northern or southern Catalonia Places * 13178 Catalan, asteroid #1 ...

and ''quinze dias'' or ''quinzena'' in Portuguese, ''quindicina'' in Italian, '' quinze jours'' or ''

quinzaine Quinzaine is a word of French language derivation: 'a quinzaine' is to Fifteen as 'a dozen' is to Twelve, and 'a trental' is to Thirty. It has various contexts of use in English. 'La quinzaine' is used in French to indicate a two week period, just ...

'' in

French French (french: français(e), link=no) may refer to: * Something of, from, or related to France ** French language, which originated in France, and its various dialects and accents ** French people, a nation and ethnic group identified with Franc ...

, and ''chenzinǎ'' in

Romanian Romanian may refer to: *anything of, from, or related to the country and nation of Romania ** Romanians, an ethnic group **Romanian language, a Romance language ***Romanian dialects, variants of the Romanian language **Romanian cuisine, traditiona ...

, all meaning "a grouping of 15"; there are also the terms ''bisettimanale'' in Italian, ''bisemanal'' in Spanish, ''bissemanal'' in Portuguese, ''bisetmanal'' in

, ''bihebdomadaire'' in

, and ''bisǎptǎmânal'' in

, that literally mean "biweekly". *

Semitic languages The Semitic languages are a branch of the Afroasiatic language family. They are spoken by more than 330 million people across much of West Asia, the Horn of Africa, and latterly North Africa, Malta, West Africa, Chad, and in large immigrant ...

have a special "doubling

suffix In linguistics, a suffix is an affix which is placed after the stem of a word. Common examples are case endings, which indicate the grammatical case of nouns, adjectives, and verb endings, which form the conjugation of verbs. Suffixes can carr ...

". When added at the end of the word for "week" it changes the meaning to "two weeks". In

Hebrew Hebrew (; ; ) is a Northwest Semitic language of the Afroasiatic language family. Historically, it is one of the spoken languages of the Israelites and their longest-surviving descendants, the Jews and Samaritans. It was largely preserved ...

, the single-word ''שבועיים'' (''shvu′ayim'') means exactly "two weeks". Also in

Arabic Arabic (, ' ; , ' or ) is a Semitic language spoken primarily across the Arab world.Semitic languages: an international handbook / edited by Stefan Weninger; in collaboration with Geoffrey Khan, Michael P. Streck, Janet C. E.Watson; Walter ...

, by adding the common dual suffix to the word for "week", ''أسبوع'', the form ''أسبوعين'' (''usbu′ayn''), meaning "two weeks", is formed. *

Slavic languages The Slavic languages, also known as the Slavonic languages, are Indo-European languages spoken primarily by the Slavic peoples and their descendants. They are thought to descend from a proto-language called Proto-Slavic, spoken during the ...

: in Czech the terms ''čtrnáctidenní'' and ''dvoutýdenní'' have the same meaning as "fortnight". In

Ukrainian Ukrainian may refer to: * Something of, from, or related to Ukraine * Something relating to Ukrainians, an East Slavic people from Eastern Europe * Something relating to demographics of Ukraine in terms of demography and population of Ukraine * So ...

, the term ''два тижні'' is used in relation to "biweekly, two weeks".

References

{{Time measurement and standards Units of time

Astronomy and tides

Analogs in other languages

See also

References