It seems like there might be a small spelling error in your request. The word you are asking about is likely "HAART," which stands for Highly Active Antiretroviral Therapy. Let me explain this term for you in a way that's easy to understand.
HAART (noun): A medical treatment that uses a combination of different medications to help people who are infected with HIV (the virus that can lead to AIDS). This therapy includes protease inhibitors and reverse transcriptase inhibitors, which work together to control the virus in the body.
HAART is an important term in the context of HIV/AIDS treatment. If you're learning English and come across this word, it's helpful to understand that it refers to a specific combination of medications that help control the virus in infected individuals.