"Race" = A group ride, characterized by many crashes, that includes both people you know and people you don't know all trying to get past a designated finish line first. Races are usually categorized to keep the most dangerous riders segregated from the riders who actually know what they're doing.
"Group Ride" or "Group Training Ride" = A race mainly among people you do know, all trying to be first past an imaginary finish line. The pace of these "group rides" is usually imperceptibly slower than that of "races," but the rate of crashing may be lower, the same, or higher.
"Cycling Team" = A collection of disparate sociopaths sharing a dangerous obsession and pretending to enjoy one another's company while secretly plotting to destroy one another. All members will, during the course of a season, put their own individual interests ahead of the team.
"Group Endurance ride" = An extended form of the "Group Ride" or "Group Training Ride" where the greater distances traveled are not allowed to translate into slower average speeds. As with all other "group rides," endurance rides must be ridden at the highest possible sustainable speed. Anyone riding at below his or her maximum speed is presumed to be a "slow rider" (see entry on "Slow rider") or is preparing for an imminent attack.
"Attack" = Where one member of the group sprints ahead of the group for as long as possible (usually, not very long). Most attacks come from riders who announce before the ride/race that they "will not attack today" or their "legs are toast." All attackers are guaranteed to win the segments of rides/races where they attack because they get to draw the imaginary finish line, which always comes just before they are recaptured and passed by the group. Another very common attack comes from a rider for whom the group has been sitting up waiting for 5+ minutes. As soon as he or she catches back on to the group, he or she attacks, so that the group can later sit up and wait for him or her again for 5+ minutes.
"Interval Ride" = A ride that starts out with a race to the interval site, followed by several "sets" of bursts of high cadence or power or both, with each set lasting anywhere from 30 seconds to 8 minutes, designed to empty the contents of one's stomach, before a final race home. Intervals are required several times a week for riders over 50 years old who are in training for ... err, ... something or other.
"No-drop ride" = A race where the ride-leader specifies before the fact that no one will be left behind. Has no bearing on the pace of the ride or whether any one gets dropped behind.
"Re-group ride" = A series of races during which the winners of one segment may or may not wait for losers to catch up.
"Recovery ride" = what most people would consider a normal, friendly (even fast) bike ride. Note: The slow pace of a "recovery ride" (16-17 mph) is not considered manly unless the ride is specifically referred to as "recovery." On "recovery rides," riders must always appear as if they could ride away from the group on a nanosecond's notice. Anyone seen riding at "recovery ride" pace on a non-recovery ride must have their team kit confiscated.
"Core training" = what most cyclists do occasionally in the off-season, but never when the weather is good enough for a ride.
"Improvement" = Occasionally refers to a rider/racer's performance, but mostly refers to bike and other equipment upgrades.
"Solo ride" = Where riders pretend they are Jens Voigt, regardless of rate of speed. Rules for solo-riding include: (a) appearing nonchalant (e.g., no hard breathing) while passing other riders traveling in the same direction; (b) looking impressive (i.e., like a pro) when passing other riders traveling in the opposite direction; and, most importantly, (c) making clear to any rider who passes you in the same direction that you are on a "recovery ride," and if you were not so diligent about your recovery, you would kick his or her ass all the way to Kansas.
"Slow rider" = a rider who does not ride as fast as they possibly can at all "group rides" other than specifically designated "recovery rides."
"Success" = Variously defined as winning a race, winning a "group ride" (or any imaginary part thereof), not crashing at all or, at least, being able to ride home from a wreck, and, most often, getting a new bike.
Other suggested entries are welcome.