What is the meaning of Bacteria?

plural of bacterium

A type, species, or strain of bacterium.

Alternative form of bacterium.

Lowlife, slob (could be treated as plural or singular).

An oval bacterium, as distinguished from a spherical coccus or rod-shaped bacillus.

bacterium

nominative/accusative/vocative plural of bactērium

bacterium

bacteria

Source: wiktionary.org