vicennial /vī-senˈyəl/

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

• lactational
• lactations
• lacteal
• lacteals
• lacteous
• lactescence
• lactescences
• lactescent
• lactic
• lactic acid
• lactiferous
• lactific
• lactifluous
• lacto-
• lactobacilli
• lactobacillus
• lactobacilluses
• lactoflavin
• lactoflavins
• lactogenic
• lactoglobulin
• lactometer
• have it coming to one
• have it in for
• have it in for someone