When a planned event/action/food/etc has a predetermined level of awesomeness which it is expected to reach. If said event/etc reaches this level it is considered to be killer. Surpassing is preferred.

very cool

A name given to someone who suddenly becomes over agressive and violent.

an adjective used to describe high quality thc based substances.

really strong weed. killer weed

1) {noun} A person (usually with self-esteem issues) who takes the lives of others
** see Murder

2){adj.} Something which is the height of cool, very stylish - ie. knocking them dead

when a person kills it all the time

A game you play with a joint or any other marijuana smoking device.
You take a hit and pass it to the next person who does the same, you have to hold in the smoke until the joint gets back to you.
This gets harder if there are more people in the circle
A variation is progressive Killer this is when you increase the amount of hits each time the J goes round the circle