A smudge of poo, crap, or shit created under the extreme conditions of wiping one’s ass while sitting on the crapper, and knowing or unknowingly smashing the cling-on against the seat and the back of the hand.
The result of missing ones ass with toilet paper, during the act of wiping.
The child was not properly trained to use the toilet, hence craped all over the toilet seat. The little Knucklesmudgling will follow in its parent’s footsteps.
The patron entered the public restroom and observed a brownish/black streak left on the toilet seat by the previous occupant, aka "Knucklesmudge".
The bulk of the human species that lives on planet earth that has no common sense otherwise known as a "Knucklesmudge".
Fogey/fogy /fougi/ sl. (early 18C+, orig. Scot) old-fashioned, stuck-in-the mud.
Person with old fashioned ideas which he is unwilling to change: Come to the disco and stop being such an old fogey!
You think me an old fogeyand an old tory, his thoughtful voice said. I saw three generations since O’Connel’s time. I remember the famine. Do you know that the orange lodges agitated for repeal of the union twenty years before O’Connel did or before the prelates of your communion denounced him as a demagogue? You fenians forget some things. (James Joyce, Ulysses. Penguin Books,1992. p. 38)