The correct answer to the question "What's up?"

In 3-dimensional Cartesian terms, the x-axis is east and west, the y-axis is north and south, and the z-axis is up and down. So the positive z-axis is what's up.

The process of methodically tipping ones shoulders so that ones breasts fluctuate in respect to their 3D coordinate spaces along the z axis sometimes having small amounts of motion in the positive x direction and both y directions.

Often titty jiggles are performed with a partner and with various types of substances lathered on to the upper quadrants or nipple area (usually defined as the unit circle in the yz plane centered at (0,0,0) )