Where does “enviroun” come from?

enviroun (Anglo-Norman) comes from Old French environ, from Old French en-, from Latin īn-, from Latin în, from Latin en, from Proto-Italic en, from Proto-Indo-European h₁én — in.

Ancestry of “enviroun”, step by step

Step	Language	Word	Meaning
1	Old French	environ	around
2	Old French	en-	en- in; into
3	Latin	īn-	un-, non-, not
4	Latin	în	in, at, on, upon, from (space)
5	Latin	en	lookǃ beholdǃ; reallyǃ?; come onǃ
6	Proto-Italic	en	in
7	Proto-Indo-European	h₁én	in

Words derived from “enviroun”

environs
environ
enviroun
disenviron

Every word from Proto-Indo-European h₁én →Every word from Latin īn- →Every word from Proto-Italic en →