Dibs is defined as a slang term for money and a slang term for a claim to something.(noun)
When you declare that the last piece of pie is yours, this is an example of a situation where you call dibs on the last piece of pie.
See dibs in Webster's New World College Dictionary
Origin: contr. < dibstone, a knucklebone or jack in a children's game < dib (< ?) + stone
See dibs in American Heritage Dictionary 4
Origin: Short for dibstones, counters used in a game
Origin: , probably from obsolete dib, to tap.
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