dibs

n. claims, rights (British slang); small amount of money (Slang); jackstones ( game in which playing-pieces [originally small bones or pebbles] are tossed and caught on the back of the hand); sweet substance or molasses of grape juice

v. dip; fish by causing the bait to bob slightly on the water

Dibs (also known as bags, bagsy, or bagsie) is a common convention used primarily in the U.S. Canada, UK and Ireland by friends or siblings to reserve or declare full or partial ownership of a community resource, such as a chair or communal food. As an example, when deciding who gets prime seating in front of a television, if there is one chair that is particularly desirable, an interested party can call "dibs" on that chair; as long as no one has previously called the chair, then it is agreed that the caller is entitled to sit there. Like advance reservations at elite restaurants, "dibs" have the economic effect of allotting a limited resource with greater preference for those who most desire it, where raising price (as with an ad-hoc auction) is undesirable. Presumably, if a resource is far more important to one person than the rest of the group, it is sensible to allot it to this person. If everyone vies equally (all "intend" to call dibs) then the exact timing serves as a lottery. Claiming Dibs on the front seat of a car is called "Calling Shotgun," Shotgun has its own distinct and separate rules that should not be confused with Dibs.
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(n.)
A sweet preparation or treacle of grape juice, much used in the East.
  

(See first dibs)

  bids