• Triannual

    Origin

    - + annual

    Full definition of triannual

    Adjective

    triannual

    1. Happening three times each year.

    Usage notes

    To avoid confusion between "triennial", once every three years, and "triannual", three times in one year, it is often better to substitute a less ambiguous phrase such as "three times a year" or "every four months".

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