Select the option that can be used as a one-word substitute for the given group of words.

Something happening in three years

Triennial

The word that can be used as a one-word substitute for the given group of words is triennial.

• Annual means happening once a year.
• Triennial means happening every three years.
• Biennial means happening every two years.
• Millennial means relating to a period of one thousand years.