The term "dibs" is an informal slang that is used to indicate a claim or reservation on something. It often expresses a desire to be the first to have or do something, as in playfully stating that one has the right to use or take something before others. For example, if you say "I have dibs on the front seat," it means you are claiming the front seat for yourself.
The word "dibs" is thought to have originated in the early 20th century, possibly derived from the phrase "to dip," which means to take or grab something quickly. It has been used in children's games and informal speech to signify a claim on something.