Where does “betaproteobacterium” come from?

betaproteobacterium (English) comes from English bacterium, from New Latin bactērium, from Ancient Greek βακτήριον, from Ancient Greek βακτηρία, from Proto-Indo-European baḱ- — club, pointed stick, peg; pointed stick, peg.

betaproteobacterium (English): Any bacterium of the class Betaproteobacteria

Definitions

Any bacterium of the class Betaproteobacteria

Ancestry of “betaproteobacterium”, step by step

betaproteobacterium traces back through two separate lines of ancestry.

via English bacterium

Step	Language	Word	Meaning
1	English	bacterium	A single celled organism with cell walls but no...
2	New Latin	bactērium	—
3	Ancient Greek	βακτήριον	Synonym of βακτηρία
4	Ancient Greek	βακτηρία	rod, staff, cane; baton
5	Proto-Indo-European	baḱ-	club, pointed stick, peg; pointed stick, peg

via English beta

Step	Language	Word	Meaning
1	English	beta	The second letter of the Greek alphabet (Β,  β), preceded by alpha (Α,  α) and followed by gamma, (Γ,  γ). In modern Greek it represents the voiced labiodental fricative sound of v found in the English words have and vase
2	Hindi	बेटा	son
3	Middle Hindi	بیٿا	—

Every word from Proto-Indo-European baḱ- →Every word from Ancient Greek βακτηρία →Every word from Ancient Greek βακτήριον →