"Opp" has multiple meanings depending on the context in which it is used. Here are some of the most common meanings:

• Opponent or Enemy: "Opp" is a slang abbreviation of the word "opponent" or "enemy." It is commonly used to refer to someone who is viewed as an adversary or someone with whom one has a conflict or disagreement.

• Outpatient Prospective Payment System (OPPS): The Outpatient Prospective Payment System (OPPS) is the system through which Medicare decides how much money a hospital or community mental health center will get for outpatient care provided to Medicare beneficiaries.

• Other Peoples Property: "Opp" is an abbreviation for "other peoples property." However, this meaning is not commonly used.

• Opposition: "Opp" is a slang word meaning opposition. It is often used by criminals to refer to their enemies, such as rival gang members. This slang isnt considered a nationwide slang, it’s mostly used in places like Pittsburgh, California, and Chicago.

It is important to note that the meaning of "opp" can vary depending on the context in which it is used.