1. plants that complete their life cycle in three years, typically growing vegetatively in the first year, continuing growth in the second year, and flowering, producing seeds, and dying in the third year
Usage: botanical term; plural form
2. events, publications, or activities that occur every three years
Usage: plural form

Examples

• The gardener planted several triennials in the back corner of the garden.
• These triennials won’t flower until their third year of growth.
• The botanical society focuses on studying triennials and their unique growth patterns.
• Art triennials have become important cultural events in major cities.
• The museum hosts triennials featuring contemporary sculpture.
• Several international triennials showcase emerging artists from around the world.