Where does “ugeiniau” come from?

ugeiniau (Welsh) comes from Welsh ugain, from Old Welsh uceint, from Proto-Brythonic ʉgėnt, from Proto-Celtic wikantī, from Proto-Indo-European h₁wih₁ḱm̥t, from Proto-Indo-European dwi(h₁)dḱm̥ti — two tens; two decades; twenty; two-ten.

ugeiniau (Welsh): twenties

Definitions

twenties

Ancestry of “ugeiniau”, step by step

Step	Language	Word	Meaning
1	Welsh	ugain	twenty; score
2	Old Welsh	uceint	—
3	Proto-Brythonic	ʉgėnt	—
4	Proto-Celtic	wikantī	twenty
5	Proto-Indo-European	h₁wih₁ḱm̥t	—
6	Proto-Indo-European	dwi(h₁)dḱm̥ti	two tens; two decades; twenty; two-ten

Every word from Proto-Indo-European dwi(h₁)dḱm̥ti →

ugeiniau — Etymology, Origin & Word History | Etymology Explorer