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

• seed leaf
• seed leaves
• seedless
• seedlike
• seedling
• seedlings
• seedlip
• seedlips
• seed-lobe
• seed-lobes
• seed money
• seed monies
• seedness
• seednesses
• seed-oil
• seed-oils
• seed oyster
• seed oysters
• seed pearl
• seed pearls
• seed-plant
• seed-plants
• seed plot
• seed plots
• seed potato