A Snaype is a character who is a king of the 3 headed snakes. It consists of 3 heads of a king cobra, python and viper. The actual body is of a dragon snake.
The act of killing a loved one or friend in order to trick your evil overlord into trusting you completely and or believing that you are their ultimate agent.
Kylo Ren totally Snape Killed his dad so that Snoke would trust him.