Norse mythology vs Ymir

Norse mythology and Ymir both are nouns.

Word	Noun	Adjective	Verb	Adverb
Norse mythology	Yes	No	No	No
Ymir	Yes	No	No	No

Norse mythology (noun)	Ymir (noun)
the mythology of Scandinavia (shared in part by Britain and Germany) until the establishment of Christianity	(Norse mythology) the primeval giant slain by Odin and his brothers and from whose body they created the world: the sea from his blood; the earth from his flesh; the mountains from his bones; the sky from his skull