HMm. I was going to say the collar of a shirt, but then there's that THING in the middle. So then I as going to say some sort of whale the with the top of its head cut off. But I can see no real reason why you would want to draw that.
It's a tooth cut in half of someone who ate so much grape candy that the insides of his tooth turned purple. That white string is some dental floss that got stuck a long time ago.
