Here's why:
* It names a concept: Mythology refers to a body of myths, legends, and stories that explain natural phenomena, historical events, or societal beliefs.
* It can be the subject of a sentence: "Greek mythology is fascinating."
* It can be the object of a verb: "I studied Norse mythology in college."
While "mythology" itself is a noun, individual words within a myth or legend can belong to other parts of speech, such as:
* Verbs: "The gods fought over the throne."
* Adjectives: "The golden apple of discord."
* Adverbs: "The hero bravely faced the dragon."