What is Tinderbox?
1.
A redhead's vagina.
The paparazzi got a great
upskirt shot of Lindsay Lohan's tinderbox.
See
2.
the literal meaning of the word is a "box for holding tinder", tinder being something combustible you use to start a fire. A tinderbox can also be a potentially dangerous situation or location.
The proper usage of the term is as an insult that sarcastically implies that somebody is 'fake tough'.
"Dang B! The Angeles National Forest is a tinderbox during the hot, arid summer."
"Hey tinderbox, wanna do something about it?"
3.
The soft bit of skin between your balls and your arsehole.
"Oh my jeans are grinding against my Tinderbox"
See