ENGLISH
REFERENCE

biennial

adj.
C1 Advanced US //baɪˈɛniəɫ// UK //baɪˈɛnɪəl// bi·en·ni·al

adj. happening once every two years. You use this to describe events like festivals or meetings that do not happen every year.

adj. occurring or appearing once every two years. Often used to describe recurring events, such as exhibitions or botanical cycles.


SIMPLE

The city hosts a biennial art festival every other summer.

CONTEXTUAL

The committee holds a biennial review to assess the long-term impact of their environmental policies.

COMPLEX

While some species are annuals, this biennial plant focuses its first year on leaf growth and its second on flowering before completing its life cycle.

Synonyms
Antonyms
Origin

Borrowed from Latin bienni(um) (“two-year period”) [from bis, bi- (“twice”) + annus (“year”)] + -al (suffix forming adjectives). By surface analysis, bi- + -ennial.

Usage

Typically used attributively before a noun. Often confused with 'biannual', which means twice a year.

Pitfall

The biennial meeting happens twice a year.The biennial meeting happens every two years.Learners often confuse 'biennial' (every two years) with 'biannual' (twice a year).

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