1810: Biweekly, Bimonthly, and Biannually Nov 28, 2019

There is ambiguity as to whether 'biweekly' or 'bimonthly' would mean "twice a week/month" or "once every two weeks/months". There is a distinction between 'biannually' (twice a year) and 'biennially'. Although there is the term 'fortnightly', this is still not a very popular one, and people opt for the clunkier "once every two weeks".

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