I was listening to [Schwarzbraun ist die Haselnuss](https://www.youtube.com/watch?v=0q7lMakwuZM) and when I looked up the word, Collins dictionary showed it’s a “(shout of) halloo” and this led me to “hallo” working as some kind of interjection, meaning as well “Halloruf” as noun and even the unexpected word “Horrido”. The dictionary kind of clarifies this all has something to do with hunting but I’m still pretty lost with all these words.