Oh wow, that's a big word! "Dharmakirtishri" is actually a combination of two names: "Dharmakirti" and "Shri". Dharmakirti was a very smart philosopher who lived a long time ago in a place called India. He wrote a lot of books about how people think and how we can know things for sure. Shri means "honorable" or "great", so people who talk about "Dharmakirtishri" are really just using two names to show a lot of respect for him.