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Mucus or Mucous?
What Is the Difference between "Mucus" and "Mucous"?
"Mucus" and "mucous" are easy to confuse because they both refer to a slimy secretion. The difference between "mucus" and "mucous" is how they are used grammatically.- "Mucus" is a noun. "Mucus" is a slimy substance secreted by the mucous membranes and glands.
- In the human respiratory system, mucus aids in the protection of the lungs.
- "Mucous" is an adjective. "Mucous" means producing or secreting mucus.
- Some mucous membranes are involved with absorption and secretion.

More about "Mucous"
The adjective "mucous" means covering or secreting mucus. It usually modifies the noun "gland" or "membrane." For example:- Mucous glands are found in several different parts of the body.
- Sodium is excreted by all mucous surfaces and by the liver and kidneys.
More about "Mucus"
The noun "mucus" denotes a slimy substance that is produced by the mucous membranes and glands. For example:- Mucus production in humans thickens in cold weather.
- Nasal mucus is usually clear and thin so it can filter air during inhalation.
UK or US Spelling?
The spelling of "mucus/mucous" is determined by whether the word is used as a noun or an adjective. The spelling is not determined by whether you're following US or UK writing conventions. In other words, "mucus/mucous" is not like pairings such as "color/colour," "favor/favour," and "neighbor/neighbour".Ready for the Test?
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