Sorry, wrong answer. The dictionary definition of "biannual" allows for
both the "half" and "every two" interpretation.

Then you need a new dictionary. Unlike "flammable" and "inflammable",
the use of "biannual" for "every two years" is incorrect. Perhaps if
enough people persist in mangling the language, it will become accepted
by the general educated populace with that meaning, but until that
happens, it just ain't right.

Jose
(yes, I know of "ain't"'s long history)
--
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