lunar cycle 
noun
Another term for Metonic cycle.Druids were early astronomers with one of the first accurate calendars based on the eighteen year lunar cycle.
- fossorial Hymenoptera
- fossula
- fossulate
- fossule
- foster
- foster-
- fosterage
- foster care
- foster child
- fosterer
- foster family
- foster father
- foster home
- Foster, Jodie
- fosterling
- foster mother
- Foster, Sir Norman
- Foster, Stephen
- fou
- Foucauldian
- Foucaultian
- Foucault, Jean Bernard Léon
- Foucault, Michel
- fouetté
- fought