Paceline - a group formation in which each rider takes a turn breaking the wind at the front before pulling off, dropping to the rear position, and riding the others' draft until at the front once again.

Panic Skid - to try with all one's will and strength to prevent an impending stack by attempting to implant one's heels as deeply as possible in the ground. Usually a dumb idea.

Pantani, Marco -An elephant-eared, Tour de France-racing, bald-headed, earring-wearing, bloody-crashing, 60-pound-weighing, spaghetti-eating FREAK! When is some smart mountain bike company going to ante up the big bucks to put this guy in just one race. Just one. The thrills. The fun. The horror.

Park tool - If you do any work at all on your bike, you probably own at least one item made by this company, the undisputed heavyweight champions of two-wheel repair. Everybody has a favorite Park Tool.

Peak - a relatively short period during which maximum performance is achieved.

Peloton - the main group of riders in a race.

Pimp - a Bike Store Guy who is always trying to sell stuff on the trail. "Blow off, pimp. If I want your opinion, I'll give it to you."

Pirelliology n. the noble art of being able to identify tires from the tracks they leave on the ground.

POD - Potential Organ Donor..

Pogo - to bounce on a full-suspension bike like a pogo stick. Also, for a full-suspension bike to bounce annoyingly and uncontrollably.

Poison oak -Back east, it's called poison ivy. If you're really allergic, you blow up like a pufferfish and die. If you're not, you just itch like crazy. Two hints: after exposure, keep your hands away from your eyes and bathing suit area. If you're really allergic, use IvyBlock, an over-the-counter drug that's the only substance approved by the FDA for fighting the nasty plants.

POS - Piece Of Shit. The antithesis to real bicycles, typified by Huffy, Murray, and any of a number of other bicycles that are poorly designed, manufactured, and assembled.

Poser - derogatory term for people with R17,000 bikes that never see an actual trail. Usually found near a trail head and never dirty. Seinfeld may be an example. Synonym for fred.

Potato Chip - a wheel that has been bent badly.

Powerslide - a two-wheel sideways slide, with the foot opposite the direction of travel kept on the ground

Prang - to hit the ground hard, usually bending or breaking something.

Prime - a special award given to the leader on selected laps during a criterium or track race, or the first rider to reach a certain landmark in a road race. It's used to heighten the action. Pronounced "preem." Privateer - an unsponsored racer.

Prune - to use one's bike or helmet to remove leaves and branches from the surrounding flora. Usually unintentional.

Pro - a rider who makes a living from his or her ability to win races and endorse products.

Pull, pull through - take a turn at the front.

Pull off - to move to the side after riding in the lead so that another rider can come to the front.

Purple -The only color on the list, and for good reason. There was a time when everything cool in off-roading was purple (the marketing term for the color was "3-D Violet."). Then, after purple played out, the cool color was blue. We're in a minimalist mode these days - black is back - but gold keeps threatening to muscle it's way in.

Purple Ano - anodized aluminum in purple. Some riders need to obtain as much of this as possible. It comes in other colors, but they are of no consequence here.

Push-Push - 1) a novice's pedaling motion, consisting of alternately pushing each foot down, instead of spinning. 2) a Shimano techno-fad shifting system.

Pusher - a rider who pedals in a large gear at a relatively slow cadence, relying on the gear size for speed.

Protaper Bars - Simply the best MX and DH Bars money can buy.