muck

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”)), from *(s)mewg, mewk 'to slip'. More at meek.

noun

1. Slimy mud, sludge.
   The car was covered in muck from the rally race.
   I need to clean the muck off my shirt.
2. Soft (or slimy) manure.
3. Anything filthy or vile. Dirt; something that makes another thing dirty.
   What's that green muck on the floor?
4. Grub, slop, swill
5. (obsolete, derogatory) Money.
6. (poker) The pile of discarded cards.
7. (Scotland, slang) Heroin.
8. (slang) Semen.

verb

1. To shovel muck.
   We need to muck the stable before it gets too thick.
2. To manure with muck.
3. To do a dirty job.
4. (poker, colloquial) To pass, to fold without showing one's cards, often done when a better hand has already been revealed.
5. (Australia, informal) To vomit.
   Move out of the way, I think I'm gonna muck.