Where does “inni” come from?

inni (Welsh) comes from Welsh i, from Middle Welsh y, from Old Welsh ir, from Proto-Celtic sindos, from Proto-Indo-European sḗm, from Proto-Indo-European sem- — together, one.

inni (Welsh): first-person plural of i

Definitions

first-person plural of i

Ancestry of “inni”, step by step

Step	Language	Word	Meaning
1	Welsh	i	I, me; to, for; that
2	Middle Welsh	y	his, its with reference to a masculine noun; triggers soft mutation of following consonant
3	Old Welsh	ir	the
4	Proto-Celtic	sindos	this
5	Proto-Indo-European	sḗm	one
6	Proto-Indo-European	sem-	together, one

Every word from Proto-Indo-European sem- →Every word from Proto-Indo-European sḗm →Every word from Proto-Celtic sindos →