sexennial /sek-senˈyəl or -senˈi-əl/

1. Lasting six years
2. Recurring every six years

• Turritella
• turtablists
• turtle
• turtleback
• turtlebacks
• turtled
• turtledove
• turtledoves
• turtle graphics
• turtleneck
• turtle-necked
• turtlenecks
• turtler
• turtlers
• turtles
• turtleshell
• turtle soup
• turtle soups
• turtle-stone
• turtling
• turtlings
• turves
• tympany
• tymps
• tynd