Slimy mud, sludge.
Heroin.
Semen.
Soft (or slimy) manure.
The pile of discarded cards.
Anything filthy or vile. Dirt; something that makes another thing dirty.
Grub, slop, swill
To manure with muck.
To shovel muck.
To vomit.
To do a dirty job.
To pass, to fold without showing one's cards, often done when a better hand has already been revealed.
The characteristic of being muddy.