I've had the same haircut for 27 years and I have no idea how to explain it to people. The closest I can come is just "standard male haircut," which most people seem to understand, but is still pretty vague.
This causes some problems whenever I go to the barber and they ask me what I want. I don't want to say "standard male haircut," because they might think I am making fun of their profession. So instead I just say, "Uh, shorter."
Thankfully, that always does the trick and I leave with exactly what I wanted. Still, I am always afraid that my requests are so vague that I'll walk away looking like one of these guys.