When you pay for goods and services in hard currency such as cheeses or honeybuns; as opposed to paying on the bubble which will eventually get your ass smashed off the yard.
1. Putting wood on a fire
2. Getting venereal disease, so that your penisburns like it is on fire.
1. Could you put a little wood on the fire, it is getting chilly in here.
2. Chaz has to get to the student health center, he got a little wood on the fire.
The Knock on Wood Card is a wooden card that's perfect to knock on if you don't have any other wood around.
Ian "I've never gotten a speeding ticket. Knock on Wood...wait there's no wood around!"
Jed "Oh yes there is, check out The Knock on Wood Card!"
Ian "That's dope, thanks Jed!"