mucous

1 of 2

adjective

mu·​cous ˈmyü-kəs How to pronounce mucous (audio)
1
: of, relating to, or resembling mucus
2
: secreting or containing mucus
3
: covered with or as if with mucus : slimy

mucous

2 of 2

nonstandard spelling of mucus

nasal mucous

Word History

Etymology

Adjective

Latin mucosus, from mucus

First Known Use

Adjective

1578, in the meaning defined at sense 1

Time Traveler
The first known use of mucous was in 1578

Phrases Containing mucous

Rhymes for mucous

See All Rhymes for mucous

Browse Nearby Words

mucoso-
mucous
mucous membrane
See all Nearby Words

Cite this Entry

“Mucous.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/mucous. Accessed 4 Sep. 2026.

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Kids Definition

mucous

adjective
mu·​cous ˈmyü-kəs How to pronounce mucous (audio)
1
: of, relating to, or resembling mucus
mucous discharges
2
: producing or containing mucus
a mucous gland

Medical Definition

mucous

adjective
mu·​cous ˈmyü-kəs How to pronounce mucous (audio)
1
: covered with or as if with mucus
a mucous surface
2
: of, relating to, or resembling mucus
a mucous secretion
3
: secreting or containing mucus
mucous glands of the intestine
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