Where does “незако́нно” come from?

незако́нно (Russian) comes from Russian незако́нный, from Russian не-, from Russian не, from Proto-Slavic ne, from Proto-Balto-Slavic nē, from Proto-Indo-European né — not; no.

Ancestry of “незако́нно”, step by step

Step	Language	Word	Meaning
1	Russian	незако́нный	—
2	Russian	не-	un-, non-, in-, im-, ir-, dis-, mis-
3	Russian	не	not, no, -n't, without; Idiomatic negative usage;...
4	Proto-Slavic	ne	not
5	Proto-Balto-Slavic	nē	—
6	Proto-Indo-European	né	not; no

Words derived from “незако́нно”

незаконнорожденный

Every word from Proto-Indo-European né →

незако́нно — Etymology, Origin & Word History | Etymology Explorer