Mucus is snot and other slime from inside your body. More specifically, mucus is a secretion of your body's mucus membranes that lubricates the inside of your body and helps protect you from bacteria. You’re welcome.

Even the history of the word mucus is gross — roots from Greek and Latin all mean “snot” and “slippery, slimy.” Mucus drips out of your nose and even slips down your throat when you’re sick. This happens because your membranes produce too much mucus when you’re sick. Mucus isn’t all bad though — your body uses it to help food go down your throat easier, and it keeps bacteria out. Mucus is gross, but germs are worse!

Definitions of mucus
  1. noun
    protective secretion of the mucus membranes; in the gut it lubricates the passage of food and protects the epithelial cells; in the nose and throat and lungs it can make it difficult for bacteria to penetrate the body through the epithelium
    synonyms: mucous secretion
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    phlegm, sputum
    expectorated matter; saliva mixed with discharges from the respiratory passages; in ancient and medieval physiology it was believed to cause sluggishness
    nasal mucus
    dried nasal mucus
    leucorrhea, leukorrhea
    discharge of white mucous material from the vagina; often an indication of infection
    type of:
    a functionally specialized substance (especially one that is not a waste) released from a gland or cell




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