If you’re just as fanatical about the luge as you are about beach volleyball, you probably know that the Olympic Games are on a biennial schedule. Every two years, either the Summer or the Winter Olympics takes place.

Don't mistake biennial for biannual, which means “twice a year.” Annoying? Yes, but other words containing the prefix bi- are even more troublesome. For example, bimonthly can mean either “twice a month” or “every two months.” To avoid confusion, you can use the prefix semi- to mean “twice during a certain time period.” So, it’s correct to say that the Olympics occurs on a biennial schedule, not on a semiannual (or biannual) one.

Definitions of biennial
  1. adjective
    occurring every second year
    “they met at biennial conventions”
    synonyms: biyearly
    periodic, periodical
    happening or recurring at regular intervals
  2. noun
    (botany) a plant having a life cycle that normally takes two seasons from germination to death to complete; flowering biennials usually bloom and fruit in the second season
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    type of:
    flora, plant, plant life
    (botany) a living organism lacking the power of locomotion
  3. adjective
    having a life cycle lasting two seasons
    “a biennial life cycle”
    “parsnips and carrots are biennial plants often grown as annuals”
    synonyms: two-year
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    annual, one-year
    completing its life cycle within a year
    lasting three seasons or more
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Word Family

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