Biweekly

Biweekly may refer to an event that occurs either twice weekly or once every two weeks. The usage "every two weeks" is more common, but both usages are common and may lead to ambiguity.^[1] There are 52 full weeks in a year of 12 months (ISO 8601 defines a year as containing 52 or 53 weeks), making for a possible 26 or 104 biweekly events in a year. This is a greater number than if such events were held twice a month, because most months have more than four weeks (28 days).

In the United Kingdom, Australia and New Zealand, the term fortnightly is more commonly used for an event that occurs every two weeks. Even in the US, a biweekly publication is issued every two weeks and a bimonthly publication is issued every two months.

It is believed, by many people growing up in the early part of the 20th century, that bi- before any of the periodic durations meant "every other" and that the opposing definition - meaning twice in such a period - is a recent faux pas, which gradually developed from wide use of those who didn't fully learn the original definition properly.

References and Notes

1. ↑ "biweekly". Online dictionary. Merriam-Webster. Retrieved 19 February 2008. 

Look up biweekly in Wiktionary, the free dictionary.

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