microbe

noun

1. Any microorganism; (loosely, nonscientifically) especially, a harmful bacterium.

   “We humans and other complex animals are full of microbes, gajillions of them. People have so many that microbe cells living in our bodies outnumber our own vastly.”

   “Yes, there are microbes everywhere and most are just fine for us, perhaps even beneficial to our microbiomes and immune systems. We don’t care about those.”