From two aspects, first, from the Roman Empire to the Middle Ages, Latin has always been the language used by the church and classical literature, and Latin was a compulsory course for all higher education at that time. So it is widely used among educated people. Second, from the characteristics of Latin itself, Latin grammar is very strict and it is a "dead" language. This does not mean that Latin has stopped using, but that Latin has stopped developing and evolving, and its meaning has been relatively fixed, which is not easy to cause ambiguity. So it is very suitable for expressing rigorous scholarship. A typical example is biology. Since Linnaeus popularized binomial method, any creature's name must be added with its Latin name, otherwise it will not be recognized.