Probiotics are the health-boosting microorganisms that make yogurt so good for you. If you have indigestion, your doctor may suggest you try taking probiotics.

Long before the term probiotic was coined, scientists noticed that people who traditionally ate yogurt had long, healthy lives. Nobel winner Élie Metchnikoff is credited with the idea that good microbes in the gut can push out the bad ones. These good microbes, in the form of food additives or supplements, got the name probiotics from the Latin pro, "for," and the Greek biōtikos, "fit for life" or "lively."

Definitions of probiotic
  1. noun
    a beneficial bacterium found in the intestinal tract of healthy mammals; often considered to be a plant
    synonyms: probiotic bacterium, probiotic flora, probiotic microflora
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    Lactobacillus acidophilus, acidophilus
    a bacterium that is used to make yogurt and to supplement probiotics
    type of:
    bacteria, bacterium
    (microbiology) single-celled or noncellular spherical or spiral or rod-shaped organisms lacking chlorophyll that reproduce by fission; important as pathogens and for biochemical properties; taxonomy is difficult; often considered to be plants
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