Where does “Terrien” come from?

Terrien (English) comes from French terrien, from French -ien, from Middle French -ien, from Old French -ien, from Latin -iānus, from Latin -ānus — Of or pertaining to; -ian.

Ancestry of “Terrien”, step by step

Step	Language	Word	Meaning
1	French	terrien	land, earth; earthly; possessing land, earth
2	French	-ien	Denotes where something or someone is from; -ian;...
3	Middle French	-ien	-ian
4	Old French	-ien	-ian
5	Latin	-iānus	—
6	Latin	-ānus	Of or pertaining to; -ian

Every word from Latin -ānus →Every word from French -ien →Every word from Latin -iānus →