Fortnight

A fortnight is a unit of time equal to 14 days (2 weeks). The word comes from the Old English: fēowertyne niht, meaning "fourteen nights".^[1][2] Some wages and salaries are paid every fortnight; however, in North America it is more common to use the term biweekly. Neither of these terms should be confused with semimonthly.

1. ↑ "Fortnight". The Concise Oxford Dictionary (5th ed.). 1964. p. 480.
2. ↑ Senight, sennight or se'night (seven-night), an old word for the week, was still in use in the early 19th century, to judge from Jane Austen's letters.