Where does “ectosymbiose” come from?

ectosymbiose (French) comes from French symbiose, from Latin symbiosis, from Ancient Greek σῠμβῐ́ωσῐς, from Ancient Greek συμβιόω, from Ancient Greek σῠν-, from Ancient Greek σύν, from Proto-Hellenic *ksún — beside, with.

ectosymbiose (French): ectosymbiosis

Definitions

ectosymbiosis

Ancestry of “ectosymbiose”, step by step

Step	Language	Word	Meaning
1	French	symbiose	symbiosis
2	Latin	symbiosis	—
3	Ancient Greek	σῠμβῐ́ωσῐς	a living together, companionship
4	Ancient Greek	συμβιόω	to live together
5	Ancient Greek	σῠν-	together; with, together
6	Ancient Greek	σύν	beside, with
7	Proto-Hellenic	*ksún	beside, with

Every word from Proto-Hellenic *ksún →Every word from Ancient Greek σῠν- →Every word from Ancient Greek σύν →