Where does “na” come from?

na (Galician) comes from Galician a, from Latin Ad, from Latin illic, from Latin ille, from Latin olle, from Proto-Italic *olnos — that.

na (Galician): Alternative form of a

Definitions

na traces back through 3 separate lines of ancestry.

Step	Language	Word	Meaning
1	Galician	a	to, toward; introduces indirect object; used to...
2	Latin	Ad	toward, to
3	Latin	illic	he, she, it, yonder, that, overthere; in that...
4	Latin	ille	that; those; "; demonstrative pronoun "; that...
5	Latin	olle	Archaic form of ille
6	Proto-Italic	*olnos	that

Step	Language	Word	Meaning
1	Galician	en	in; When preceding a complement of a verb it can...
2	Old Portuguese	en	in
3	Latin	în	in, at, on, upon, from (space)
4	Latin	en	lookǃ beholdǃ; reallyǃ?; come onǃ
5	Proto-Italic	en	in
6	Proto-Indo-European	h₁én	in

Step	Language	Word	Meaning
1	Galician	non	no, not, not at all; no
2	Old Portuguese	non	no, not
3	Latin	nōn	not
4	Old Latin	noenum	—
5	Proto-Indo-European	óynos	one; single