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biquarterly

American  
[bahy-kwawr-ter-lee] / baɪˈkwɔr tər li /

adjective

  1. occurring twice in each quarter of a year.


biquarterly British  
/ baɪˈkwɔːtəlɪ /

adjective

  1. occurring twice every three months

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of biquarterly

First recorded in 1880–85; bi- 1 + quarterly