Where does “tricennial” come from?

tricennial (English) comes from Latin tricennium, from Latin trīcennis, from Latin trīciēs, from Latin annus, from Proto-Italic atnos, from Proto-Indo-European h₂et-no-, from Proto-Indo-European h₂et- — grass.

tricennial (English): Of or pertaining to thirty years; occurring once...

Definitions

  1. Of or pertaining to thirty years; occurring once...

Ancestry of “tricennial”, step by step

StepLanguageWordMeaning
1Latintricenniumthirty years
2Latintrīcenniscelebrated or occuring every thirty years, tricennial
3Latintrīciēsthirty times
4Latinannusyear; time; season
5Proto-Italicatnosyear
6Proto-Indo-Europeanh₂et-no-—
7Proto-Indo-Europeanh₂et-grass
Every word from Proto-Indo-European h₂et- →Every word from Proto-Indo-European h₂et-no- →Every word from Proto-Italic atnos →