Translation: "Meccos=Sperm Labios=Lips"
1. A person so absolutely beyond hope, so utterly devoid of any intellectual value, that they are beyond all other insults. This is the pinnacle insult for someone.
2. Someone who is simply stupid, uninformed, or otherwise "not getting it" to such a degree that no other insult will do.
Ex. 2. "You saw your cousin's face on her vagina, man. Of course she is cheating, you stupid meccoslabios!"