Similar to "Fives" or calling "shotgun", "Quack Quack Seatback" is a common way to lay short-term claim to a seat you're about to vacate when with a larger group. Sometimes shortened to "Quacks."
Person A: "Hey, you stole my seat."
Person B: "It's my seat now."
Person C: "No, he called Quack Quack Seatback. Move it."
When leaving a chair, you can say "I call seatback" and no oneelse in the room can take the seat away from you. Similar to saying, "I call shotgun" when approaching a car.
when leaving a seat calling seatbacks before someone else sits in it gets you your seat back upon returning. If you sit somewhere else, or go outside than seatbacks is nullified.
A generally large, overweight, or obese person usually compared to a whale that has been harpooned by a ship and got away. Basically entailing that the person is as big as a whale, and has scars on their back just like a once harpooned whale.
There are many different breeds that include:
Bearded scarback
Albino scarback
etc...
Holy shit Marv! Did you see the size of that scarback!
That scarback had the largest fupa i have ever seen!