From Middle English mok, muk, from Old Norse myki, mykr (“dung”) or less likely Old English *moc, *moce (in hlōsmoc (“pigsty dung”) and lustmoce (“lady's smock (Cardamine pratensis)”)) (compare Icelandic mykja and Danish møg ("dung")), from Proto-Germanic *mukį̄ (“dung; manure”), from Proto-Germanic *muk-, from Proto-Indo-European *(s)mewg-, *mewk- (“slick, slippery”) (compare Welsh mign (“swamp”), Latin mūcus (“snot”), mucere (“to be moldy or musty”), Latvian mukls (“swampy”), Albanian myk (“mould”), Ancient Greek μύξα (múxa, “mucus, lamp wick”), Ancient Greek μύκης (múkēs, “mushroom”), German Mauke (“mud fever”)), from *(s)mewg, mewk 'to slip'. More at meek.
Also, Figuratively, Usually Anything filthy or vile. Dirt; something that makes another thing dirty.
What's that green muck on the floor?
"I am so happy to be away from all the muck," she [Melinda French Gates] said, adding elsewhere in the interview: "Whatever questions remain there of what - I can't even begin to know all of it - those questions are for those people and for even my ex-husband.2026 February 25, Ben Hatton, quoting Melinda French Gates, “Bill Gates 'took responsibility' over Epstein ties in staff meeting, foundation says”, in BBC:
the fatal muck we quarrell'd forc. 1622, John Fletcher, Philip Massinger, “The Sea-Voyage. A Comedy.”, in Comedies and Tragedies […], London: […] Humphrey Robinson, […], and for Humphrey Moseley […], published 1647, →OCLC, Act V, scene ii:
Ah blurt oot ma muck n pull oot.1994 [1993], Irvine Welsh, “Bang to Rites”, in Trainspotting, London: Minerva, →ISBN, page 219:
10
Usually Food, especially that eaten quickly.
Ottawa Valley Dialect
Does I need fur t' mek som muck fur yis two?
muck
verb
Etymology
From Middle English mok, muk, from Old Norse myki, mykr (“dung”) or less likely Old English *moc, *moce (in hlōsmoc (“pigsty dung”) and lustmoce (“lady's smock (Cardamine pratensis)”)) (compare Icelandic mykja and Danish møg ("dung")), from Proto-Germanic *mukį̄ (“dung; manure”), from Proto-Germanic *muk-, from Proto-Indo-European *(s)mewg-, *mewk- (“slick, slippery”) (compare Welsh mign (“swamp”), Latin mūcus (“snot”), mucere (“to be moldy or musty”), Latvian mukls (“swampy”), Albanian myk (“mould”), Ancient Greek μύξα (múxa, “mucus, lamp wick”), Ancient Greek μύκης (múkēs, “mushroom”), German Mauke (“mud fever”)), from *(s)mewg, mewk 'to slip'. More at meek.
1
To shovel muck from.
We need to muck the stable before it gets too thick.
2
To manure with muck.
3
To do a dirty job.
4
Card games, PokerColloquial To pass, to fold without showing one's cards, often done when a better hand has already been revealed.
Etymology From muck, as a play on mud (“a mucky substance”) and MUD (“multi-user dungeon”). Various backronyms have been invented but are not the true origin.
1
Internet A kind of textbased online roleplaying game incorporating social interaction and allowing players to extend the environment with new rooms, objects, etc.