muck

American  

[muhk] / mʌk /

noun

1. moist farmyard dung, decaying vegetable matter, etc.; manure.

2. a highly organic, dark or black soil, less than 50 percent combustible, often used as a manure.

3. mire; mud.

4. filth, dirt, or slime.

5. defamatory or sullying remarks.

6. a state of chaos or confusion.

   to make a muck of things.

7. Chiefly British Informal. something of no value; trash.

8. (especially in mining) earth, rock, or other useless matter to be removed in order to get out the mineral or other substances sought.

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verb (used with object)

1. to manure.

2. to make dirty; soil.

3. to remove muck from (sometimes followed byout ).

4. Informal.

   1. to ruin; bungle (often followed byup ).

   2. to put into a state of complete confusion (often followed byup ).

verb phrase

1. muck about / around to idle; waste time; loiter.

muck British  

/ mʌk /

noun

1. farmyard dung or decaying vegetable matter

2. Also called: muck soil.  an organic soil rich in humus and used as a fertilizer

3. dirt or filth

4. earth, rock material, etc, removed during mining excavations

5. slang rubbish

6. See Lord Muck Lady Muck

7. slang to ruin or spoil

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verb

1. to spread manure upon (fields, gardens, etc)

2. to soil or pollute

3. (often foll by out) to clear muck from

Etymology

Origin of muck

1200–50; Middle English muc, muk < Old Norse myki cow dung

Explanation

Muck is a goopy, muddy substance, like the muck at the bottom of a pond or the muck you clean out of the gutters on your house once a year. You can also use muck to mean animal manure, its original, 13th-century meaning — specifically, "cow dung and vegetable matter used as manure." The definition has expanded since then to include any number of dirty, slimy substances, from the mud on the bottom of a lake to the sludge in a flooded basement. As a verb, to muck is either to remove animal waste or to spread manure on a field.

Example Sentences

A woman, in a rhinestone shirt, told me that she wanted to convene her fellow cyclists to whizz by the gulleys and alleyways around Tucson, searching for clues in the muck.

From Slate • Feb. 23, 2026

The streets of America did not need to be paved with gold; it would suffice to be less mired in muck.

From The Wall Street Journal • Jan. 16, 2026

“Like slime, sludge, and muck, slop has the wet sound of something you don’t want to touch,” the editors continued.

From Salon • Jan. 13, 2026

There is, ultimately, only so much cow muck to feed the system.

From BBC • Dec. 17, 2025

Breathless and stunned, I wander the trove, struggling to walk within the muck that fills the space between treasure piles.

From "Challenger Deep" by Neal Shusterman

Related Words

• dirt
• goo
• gunk
• manure
• mud
• slime
• sludge
• trash