Pronounced to rhyme with “put”, the word refers to the culmination of black and nasty shit that accumulates on one’s feet after transversing unclean ground without any shoes or any similarly functioning accessory of clothing.
Particularly on surfaces such as concrete and asphalt.
Matthew: Jack, please put some fucking shoes on before walking to McDonalds or you’ll end up with nu’ut all over your feet.
Jack: Don’t be silly.