A pathogen is a tiny living organism, such as a bacterium or virus, that makes people sick. Washing your hands frequently helps you avoid the pathogens that can make you sick.

Pathos is the Greek word for disease and -genes means "born of." So, a pathogen is something that causes disease, like a virus like the rhinovirus, which causes the common cold. At summer picnics, people are cautious about keeping certain foods like potato salad in coolers with ice — the eggs in such dishes spoil quickly out in the heat, introducing pathogens that can make people sick.

Definitions of pathogen
  1. noun
    any disease-producing agent (especially a virus or bacterium or other microorganism)
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    type of:
    micro-organism, microorganism
    any organism of microscopic size
    infectious agent, infective agent
    an agent capable of producing infection
Word Family

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