biennial /bī-enˈi-əl or -enˈyəl/

1. Lasting two years
2. Happening or appearing once in two years

1. A plant that flowers and fruits only in its second year, then dies
2. An event taking place or being celebrated every two years

biennˈially adverb

• nievefuls
• nieves
• nievie-nick-nack
• nievie-nievie-nick-nack
• nife
• nifedipine
• nifes
• niff
• niffed
• niffer
• niffered
• niffering
• niffers
• niffier
• niffiest
• niffing
• niffnaff
• niffnaffed
• niffnaffing
• niffnaffs
• niff-naffy
• niffs
• niffy
• niffy-naffy
• Niflheim