The point in a romantic relationship when pictures of the couple begin to appear on Facebook, and or when the relationship status changes to "In a relationship".

The safeguarding of Earth and other worlds from biological cross-contamination (i.e. billionaires with too much time on their hands).

Also known as “planetary protection.” Planetary protection / quarantine “reflects both the unknown nature of the space environment and the desire of the scientific community to preserve the pristine nature of celestial bodies until they can be studied in detail.”

There are two types of interplanetary contamination. Forward contamination is the transfer of viable organisms from Earth to another celestial body. Back contamination is the transfer of extraterrestrial organisms, if such exist, back to the Earth's biosphere.

Your update feed on facebook. The place where you start when signing into facebook or go to when clinking the "home" tab. The place where you see all of your facebook friends updated status and such if you haven't blocked them.

the act of facebooking that resembles the use use of freebasing cocain. Hours of use that leaves you feeling empty inside. Feeling powerless to say no from compulsive checking to see if any one has made a comment. Repeated comments on your own posts.

That point in a relationship at which people engage in oral sex hence applying their faces to the other's home bases.

Your friends on Facebook. Can also be a verb. Facebasing.