Synonyms/Hypernyms (Ordered by Estimated Frequency) of noun biennial

1 sense of biennial

Sense 1
biennial -- ((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)
       => plant, flora, plant life -- ((botany) a living organism lacking the power of locomotion)

Antonyms of adj biennial

2 senses of biennial

Sense 1
biennial (vs. perennial) (vs. annual), two-year -- (having a life cycle lasting two seasons; "a biennial life cycle"; "parsnips and carrots are biennial plants often grown as annuals")

perennial (vs. annual) (vs. biennial) -- (lasting three seasons or more; "the common buttercup is a popular perennial plant")
annual (vs. biennial) (vs. perennial), one-year -- (completing its life cycle within a year; "a border of annual flowering plants")

Sense 2
biennial, biyearly -- (occurring every second year; "they met at biennial conventions")

INDIRECT (VIA periodic) -> aperiodic, nonperiodic -- (not recurring at regular intervals)

Similarity of adj biennial

2 senses of biennial

Sense 1
biennial (vs. perennial) (vs. annual), two-year -- (having a life cycle lasting two seasons; "a biennial life cycle"; "parsnips and carrots are biennial plants often grown as annuals")

Sense 2
biennial, biyearly -- (occurring every second year; "they met at biennial conventions")
       => periodic (vs. aperiodic), periodical -- (happening or recurring at regular intervals; "the periodic appearance of the seventeen-year locust")