bacteria

noun3

1. •
   A type, species, or strain of bacterium.

   • Anaerobic bacteria function in the absence of oxygen, where as aerobic bacteria require sunlight and also oxygen. Both these bacterias are capable of breaking down the organic matter […] — 2002
2. •
   (slang, offensive) Lowlife, slob (could be treated as plural or singular).
3. •
   (old-fashioned) An oval bacterium, as distinguished from a spherical coccus or rod-shaped bacillus.