I assume the suffix "-saur" refers to a dinosaur. Then, what does the prefix "Humungous" mean?

Native speaker’s answer
Rebecca
"Humungous" is not a prefix, it is actually a word that means "huge"! Here, it has been used to indicate that the dinosaur is really, really big. Ex: Wow, your dog is humongous! It looks bigger than me. Ex: This is a humungous burger. I don't think I'll be able to finish.