Bacillus and Microbe

Bacillus noun - Aerobic rod-shaped spore-producing bacterium; often occurring in chainlike formations; found primarily in soil.

Microbe is a synonym for bacillus in bacterium topic. In some cases you can use "Microbe" instead a noun "Bacillus", when it comes to topics like thing, germ, micro-organism.

Microbe noun - A minute life form (especially a disease-causing bacterium); the term is not in technical use.

Bacillus is a synonym for microbe in microorganism topic. You can use "Bacillus" instead a noun "Microbe", if it concerns topics such as thing, germ, bacteria, bacterium.