An unwanted friend who feeds off of the company of a care giver. The fetus is usually the outcast of a group of friends. In most cases, one friend feels bad for the fetus, and gives him company and false friendship. This term is called feeding. In turn, the fetus will will contribute nothing back to the care giver(only because the "fetus" is a loser and cannot possibly contribute anything). The care giver will often get fed up with the fetus when he becomes too attached. Many care givers turn to the method of negative feeding. This happens when the care giver decides to use the fetus as a tool to rid of the fetus. Often involves using the fetus for rides, money, food, beer, or even using the fetus as the butt of all jokes for humor. This often turns into an abortion. This is when the fetus becomes so weak and hurt he either cuts the tie or is pushed out by the care giver. The care giver is often referred to as the UC or umbilca cord. This is a seprate matter.
The plural usage for fetus is the term "feti".
"Hey Dan, you really need to get rid of that fetus! He is really weighing you down man!"
"Dude, why are you so nice to that faggot asian kid? Your just using him as a fetus, because you feel bad for him. Just cut the damn cord, and get rid of that kid!"