Bi-weekly

A fortnight is a unit of time equal to 14 days (2 weeks). The word derives from the Old English: fēowertyne niht, meaning "fourteen nights".

Some wages, salaries, and social security benefits are paid on a fortnightly basis; however in North America it is far more common to use the term . Neither of these terms should be confused with , which divides a year into exactly 24 periods (12 months × 2), instead of the 26 (≈52 weeks ÷ 2) of fortnightly/biweekly.

In astronomy, a fortnight is half a synodic month, the mean time between a full moon and a new moon (and vice versa). This is equal to 14.77 days.

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.

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