: occurring every two years <a biennial celebration>
: growing stalks and leaves one year and flowers and fruit the next before dying
Word Root of BIENNIAL
The Latin word annus, meaning “year,” gives us the root ann or enn. Words from the Latin annus have something to do with a year. Anything that is annual happens once a year and anything biennial happens once every two years. An anniversary is the return every year of the date on which something special happened. Something perennial continues all year long or comes back each year.