English

endosymbiont

From endo- + symbiont.

Proto-Indo-European *h₁n̥dóm ‘inside’

Proto-Hellenic *éndon

Ancient Greek ἔνδον ‘inner’

English endo-

Today it means

noun An organism that lives within the body or cells of another organism.

Language periods are conventional ranges, not dates for this word.

Etymograph / endosymbiont