Meaning of BIENNIAL in English

I. (ˈ)bī|enēəl, -nyəl adjective

Etymology: Latin bienni um period of two years (from bi- + -ennium, from annus year) + English -al — more at annual

1. : occurring, appearing, or being made, done, or acted upon every two years — compare biannual

2. : continuing or lasting for two years — used specifically of plants (as the parsnip) that require two growing seasons in which to go from seed to seed; compare annual

II. noun

( -s )

: something that is biennial (as an exhibition or examination) ; especially : a biennial plant

Webster's New International English Dictionary.      Новый международный словарь английского языка Webster.