When sharing a spliff, when you have to pass it, hold it out to the next person. if they do not realise the spliff is there after a minute or so you pass it to the person after them. the person who has the spliff takes a drag and says "Toothed".
The person who just missed the spliff has been toothed.

Toothing is a technological evolution of the sexual practice known as "dogging". People with Bluetooth enabled mobile devices broadcast to other Bluetooth enabled devices in the area that they are "up for a shag" They text some flirtatious sexual banter back and forth for a bit, then arrange to meet up for an impromptu shag in the nearest nook or cranny.

i can't believe there's no definition for tooth

(n.) Having sex between strangers, after having been arranged via the mobile phone (cell phone) using Bluetooth technology.

It's something in your mouth that's hard and white

A Nice piece of crystal meth shaped like a real tooth (usually a large animals or shark), with a diluted but clear color.

cleanable mouth bone