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biennial / biannual
Nov. 6th, 2018 08:38 ambiennial (bai-EN-ee-uhl) - adj., happening every two years; lasting two years.
biannual (bai-AN-yoo-uhl) - adj., happening twice a year; happening every two years.
And yes, this is confusing -- and getting confused is how the second became a synonym for the first. The mnemonic I use is that plants that live two years are only called biennials, not biannuals (just as many-season plants are perennials, not perannuals) -- so that's the one to use for every two years. If you want to avoid the confusing word entirely, you can use semiannual. Both are from Latin roots bi-, two/twice + annus, year, where the different spelling come about because biennial was put together in Latin, which has some vowel change rules when it comes to stems, and biannual was put together in English, which doesn't.
---L.
biannual (bai-AN-yoo-uhl) - adj., happening twice a year; happening every two years.
And yes, this is confusing -- and getting confused is how the second became a synonym for the first. The mnemonic I use is that plants that live two years are only called biennials, not biannuals (just as many-season plants are perennials, not perannuals) -- so that's the one to use for every two years. If you want to avoid the confusing word entirely, you can use semiannual. Both are from Latin roots bi-, two/twice + annus, year, where the different spelling come about because biennial was put together in Latin, which has some vowel change rules when it comes to stems, and biannual was put together in English, which doesn't.
---L.
