vicennial /vī-senˈyəl/

1. Lasting, or coming at the end of, twenty years
2. Occurring every twenty years

• slanderer
• slanderers
• slandering
• slanderous
• slanderously
• slanderousness
• slanderousnesses
• slanders
• slane
• slanes
• slang
• slanged
• slanger
• slangers
• slangier
• slangiest
• slangily
• slanginess
• slanginesses
• sesamoids
• sese
• seseli
• seselis
• sesey
• sesh