Extremely small, visible only through a microscope, or incredibly tiny in size.
From Greek "mikros" (small) and "skopein" (to look at). The word was created in the 17th century when microscopes were invented, combining roots to describe what the instrument reveals.
The microscopic world is so strange that bacteria can have virus predators called bacteriophages—you could have viruses attacking bacteria inside your body, revealing hidden ecosystems of predator and prey!
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