The story
- Proto-Indo-European*h₁éǵʰ
- Proto-Indo-European*h₁éǵʰs
- Proto-Indo-European*h₁eǵʰsteros
- Proto-Italic*eksteros
- Latinexter
- Latinextrā
- Englishextra-
- Ancient Greekβακτηρία (baktēría)
- Ancient Greekβακτήριον (baktḗrion)
- New Latinbactēria
- Englishbacteria
- Proto-Indo-European*h₂el-
- Proto-Indo-European*h₂élisder.?
- Englishbacterial
- Englishbacterially
- English todayextrabacterially
From extra- + bacterially.
Etymology from Wiktionary, CC BY-SA 4.0.