Absurdist recursion of "to cum" - to ejaculate, by translating the latin preposition "cum" meaning "with" like in "magna cum laude".
(2) Acronym, WITH - standing for "What in the hell", useable akin to WTF
(3) Noun (uncountable), with - sperm, ejaculate
Stemming from the same absurdist thought process
A: "She told me to pull out, but I accidentally withed inside her"
B: "Dude, I was totally watching her webcam show and withed all over my keyboard when I saw her with!"
A: "WITH? Why would you do that?"
B: "WITH... That is such a silly and stupid way to say cum."
A: "Shit man, my with is probably in her womb now..."
B: "Oh, shut up and eat my with."