A combination of the words "shit" and "hitbox." Used to refer to a hitbox that doesn't match the animation or doesn't make sense, like a weapon that deals damage to you but misses you in the animation. Such an occurrence caused by lag does not make it a shitbox.
A car or vehicle that is musty smelling, over 200k miles, comes with a check engine either new, or bought used. This type of car cannot exceed over 40 miles an hour without shaking to death. It also can come with multiple soda cans and cigarettes inside as a bonus when bought.