Fortnight

If you have heard the term "fortnight" used it probably meant a unit of time equaling 2 weeks as in 14 consecutive days.

The word suggest a fort as in fortress, but that is not the origin.

The word derives from Old English: fēowertyne niht, a term meaning "fourteen nights".

Some wages and salaries are paid on a fortnightly basis. In North America, it is more common to use the term "biweekly."

Neither of these terms should be confused with "semimonthly" which divides a year into exactly 24 periods instead of the 26 periods of fortnightly or biweekly.

In astronomy, a fortnight is half a synodic month, equivalent to the mean time between a full moon and a new moon (and vice versa). This is equal to 14.77 days. The synodic period is the amount of time that it takes for an object to reappear at the same point in relation to two or more other objects.