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.

Definitions of muck
  1. noun
    any thick, viscous matter
    synonyms: goo, gook, goop, guck, gunk, ooze, slime, sludge
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    sludge (rich in organic matter) that accumulates at the bottom of lakes or oceans
    type of:
    that which has mass and occupies space
  2. noun
    fecal matter of animals
    synonyms: droppings, dung
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    show 4 types...
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    buffalo chip, chip, cow chip, cow dung
    a piece of dried bovine dung
    fossil excrement; petrified dung
    pigeon droppings
    droppings of pigeons
    cow pie, cowpie
    fecal matter of a cow
    type of:
    BM, dejection, faecal matter, faeces, fecal matter, feces, ordure, stool
    solid excretory product evacuated from the bowels
  3. verb
    remove muck, clear away muck, as in a mine
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    type of:
    remove, take, take away, withdraw
    remove something concrete, as by lifting, pushing, or taking off, or remove something abstract
  4. verb
    spread manure, as for fertilization
    synonyms: manure
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    type of:
    scatter, spread, spread out
    strew or distribute over an area
  5. verb
    soil with mud, muck, or mire
    “The child mucked up his shirt while playing ball in the garden”
    synonyms: mire, muck up, mud
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    type of:
    begrime, bemire, colly, dirty, grime, soil
    make soiled, filthy, or dirty
Word Family

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