Where does “trienio” come from?

trienio (Galician) comes from Latin triennium, from Latin triennis, from Latin annus, from Proto-Italic atnos, from Proto-Indo-European h₂et-no-, from Proto-Indo-European h₂et- — grass.

trienio (Galician): triennium; period of three years

Definitions

triennium; period of three years

Ancestry of “trienio”, step by step

Step	Language	Word	Meaning
1	Latin	triennium	a period of three years, triennium
2	Latin	triennis	three-year-old
3	Latin	annus	year; time; season
4	Proto-Italic	atnos	year
5	Proto-Indo-European	h₂et-no-	—
6	Proto-Indo-European	h₂et-	grass

Every word from Proto-Indo-European h₂et- →Every word from Proto-Indo-European h₂et-no- →Every word from Proto-Italic atnos →