proteobacterial

Etymology tree
Ancient Greek Πρωτεύς (Prōteús)bor.
New Latin Prōteusder.
taxonomic name proteo-
Ancient Greek βακτηρία (baktēría)
Proto-Indo-European *-yósder.
Ancient Greek -ῐος (-ĭos)?
Ancient Greek -ιον (-ion)
Ancient Greek βακτήριον (baktḗrion)der.
taxonomic name Bacteria
taxonomic name Proteobacteria
Proto-Indo-European *h₂el-der.?
Proto-Italic *-ālis
Latin -ālisbor.
Old French -albor.
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Latin -ālis
Old French -elbor.
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Latin -ālisbor.
Middle English -al
English -al
English proteobacterial
From taxonomic name Proteobacteria + English -al.