App has a beautiful and simple interface. The best choice for a pocket dictionary that is always at hand. From this, you can learn a lot of new and interesting things. Bacteria common noun bacteria, singular bacterium constitute a large domain of prokaryotic microorganisms. Typically a few micrometers in length, bacteria have a number of shapes, ranging from spheres to rods and spirals. Bacteria were among the first life forms to appear on Earth, and are present in most of its habitats. Bacteri