As the story goes, Liefeld sent this drawing of a “new character” to writer Fabian Nicieza, who responded that it was nothing but a copy of the DC character Deathstroke. So Nicieza dubbed the character “Deadpool,” because, logically, a deadpool is where you’d be most likely to find people doing the deathstroke.
Much like DC’s character Lobo, Deadpool quickly became a parody of the kind of ultraviolent antiheroes popular at the time, like Wolverine and the Punisher. Also like Lobo, Deadpool became superpopular among irony-blind comics readers, making him (as far as I can tell) the only new non-Turtle superhero to gain mainstream recognition for Stan knows how long. Seriously, if you can think of another superhero that was introduced since Deadpool in 1993 and would be recognizable to your average non-nerd person on the street, I want to hear about them).