The longest and widest pussy, that comes out of nowhere.

When you shamelessly let one rip so violently those in your vicinity can feel the vibration.

When a woman in Alaska thrashes about the bed having multiple orgasms prompted by her Rotating G-Spot Rabbit Vibrator. Always involves loud moaning, or perhaps a biting of a pillow if the kids are home and not asleep. It feels as though the earth moves uncontrollably.

When the number of stumbling drunk people has surpassed a threshold that gives the sitting spectator the impression that an earthquake is occurring.

Orgasms.

The act of standing with legs shoulder width apart, knees bent slightly, arms relaxed at sides and proceeding to shake rapidly but ever so slightly. Usually performed in locker rooms, while wearing only boxers.

If looking to perform the act, one should do so to the theme from cell phone 'tetris'.

Made famous by Ben Tumin, of ten minute striker fame.

A spontaneous reaction to absolutely nothing which involves one individual of the group declaring the act and the other members acknowledging the declaration by flailing themselves at nearby walls while yelling 'earthquake party,' along with sounds that compliment the smashing of one's body into walls as if an earthquake were occurring.