Biweekly

Biweekly may refer to occurring twice a week, or occurring every two weeks. Due to this ambiguity, many style guides recommend to never use the term and to replace with unambiguous expressions. 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. In the US, a biweekly publication is issued every two weeks and a bimonthly publication is issued every two months. New York State SNAP refers to a biweekly paycheck as every 2 weeks.

Traditionally in the english used in the US, "bi" as a word prefix meant two, or every two. An example would be Bicentennial = two hundred years. For splitting a unit of measure in two, "semi" was used. A common example is Semi-annual = two times a year. In keeping with this construct of english, Biweekly would mean every two weeks.

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