adjective Also biyearly (for defs 1, 2).
Examples from the Web for biennial
Those are results of the biennial Chicago Council on Global Affairs survey of public opinion on foreign policy (PDF).
At the Biennial, only a very few artworks escape to stand on their own.
She had similar fears when 2010 Biennial curators Bonami and Gary Carrion-Murayari came calling last year.
Famous in history by the biennial meetings of the Blackmailers' Club.The Roycroft Dictionary|Elbert Hubbard
Endive, en′div, n. an annual or biennial plant of the same genus as chicory, used as a salad.
In 1877 the constitution was amended by providing for biennial, instead of annual, sessions of the legislature.The History of Minnesota and Tales of the Frontier|Charles E. Flandrau
In its natural state, this is a perennial plant; but, when cultivated, it is generally treated as an annual or as a biennial.The Field and Garden Vegetables of America|Fearing Burr
In South Carolina they are biennial—as is proposed in the federal government.The Federalist Papers|Alexander Hamilton, John Jay, and James Madison
British Dictionary definitions for biennial
Word Origin and History for biennial
"lasting for two years" (1620s); "occurring every two years" (1750), from Latin biennium "two-year period," from bi- (see bi-) + annus "year" (see annual). The vowel change is "due to the Latin phonetic law according to which the unaccented and closed radical syllable of the second element of compounds, original -ă- becomes -ĕ-" [Klein]. The noun meaning "a biennial plant" is attested by 1770.