A fortnight is a unit of time equal to 14 days (2 weeks). The word derives from the Old English term fēowertīene niht, meaning "fourteen nights" (or "fourteen days," since the Anglo-Saxons counted by nights).
Semitic languages have a special "doubling suffix". When added at the end of the word for "week" it changes the meaning to "two weeks". In Hebrew, the single-word שבועיים (shvu′ayim) means exactly "two weeks". Also in Arabic, by adding the common dual suffix to the word for "week", أسبوع, the form أسبوعين (usbu′ayn), meaning "two weeks", is formed.
Slavic languages: in Czech the terms čtrnáctidenní and dvoutýdenní have the same meaning as "fortnight". In Ukrainian, the term два тижні is used in relation to "biweekly, two weeks".
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