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

If sweeping appeals to our collective empathy have failed to resonate—if the public is not moved by Randy Fine’s intersectional shortcomings—maybe we are better off getting down in the muck.

From Slate • Feb. 12, 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

One dairy farmer who turns his cattle waste into biomethane, describes cow muck as "nature's crude oil".

From BBC • Dec. 17, 2025

One man, pulling an anchor off Naushon, hooked an old crown that had been buried in the muck for a century.

From "Beyond the Bright Sea" by Lauren Wolk

Related Words

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