biannual

adj

1. (not-comparable)Occurring twice a year; semiannual.

   “The annual values were disaggregated into biannual values. Then the biannual values were disaggregated into quarterly values. Finally the quarterly values were disaggregated into the desired monthly values.”

   “Collection of papers presented at the workshops during the 1988 biannual symposia in February (New Orleans) and May (Innsbruck).”

   “[…] the biannual meetings between the President of the European Council and the President of the United States were formalized, there were to be two meetings per year […]”

   “Biannual newsletter / The Society publishes a twice yearly newsletter, called "Headlines".”

   “Under a lease, Abel is required to make biannual rent payments, one in January and one in July[…].”

2. (not-comparable, proscribed)Occurring once every two years; biennial.

   “The relative share of agriculture in GDP of the West Bank (calculated on the basis of fixed 1986 prices, and as a two-year average to deal with the major biannual fluctuations in olive production) declined[…].”

   “Thus he argues that the members of the National Assembly were independent from the constituencies that elected them, because the latter (the assemblies, administrative and elected) are "biennially renewed," as was the National Assembly. […] This [being responsible to electors] is implicitly the case of the representatives in the National Assembly, who must also face biannual elections[…].”

   “Now, after having solved the biannual period problem back to period one of the ten biannual periods, i.e. quarters 77–84 it is necessary to convert the state variables, namely n, SK and GK, from biannual to annual units.”

   “"The Earth Charter opens a new phase[…]." (Mikhail Gorbachev, as quoted in The Earth Charter Initiative, Biannual Report 2002–2003, Earth Charter International Secretariat, http://www.earthcharter.org/files/resources/Biannual%20Report.pdf, p 10,[…]).”

noun

1. Something occurring twice each year.

   “It was a biannual from April 1970 to October 1977 and has been a quarterly since fall 1978.”