Why is two weeks called a fortnight?
The fortnight is a unit of time equivalent two weeks that is 14 consecutive days, or literally 14 nights The word derives from the Old English feorwertyne or (feowertiene) niht, meaning “fourteen nights. The strong accent and the rapid pronounciation made it sound like ‘fortnight’. The term is common in the British Isles and many Commonwealth countries such as Australia where many wages, salaries and most social security benefits are paid on a fortnightly basis. Fortnight is rarely used in North America. Millifortnights (about 20 minutes) and nanofortnights (1.2096 milliseconds) have also been used occasionally in computer science, usually in an attempt to be deliberately over-complex and obscure. The aim is generally to slow users down, allowing them to set parameters only after some thought. One attoparsec per microfortnight is approximately 1.00432766 inches per second.
