Hui (Хуй) is a derogatory name of male reproductive organ in Russian. It's an incredibly common word in Russian-speaking countries and has quite a lot of (deragotory) meanings and can be used to describe numerous actions. Common phrases: "Пошел на хуй", "Идите пожалуйста нахуй"(approx. "fuck you"), "Дохуя" ("shitload"), "Похую" ("fuck it", as in "don't care"), "Хуёво" ("fucking bad"), "Нихуя себе" ("fuck me", extreme surprise), "Нахуя?" ("for fucking what?").