You probably don't know that:

1. The day after tomorrow is called Overmorrow.

2. The first cry of a new born baby is called Vagitus


3. Your little toe or finger is called Minimus


4. The dot over an "i" or a "j" is called Tittle


5. When your stomach rumbles, that's a Wamble

Below are other words which most people presumably don't know exist.