Ygdrasil vs Yggdrasil

Ygdrasil and Yggdrasil both are nouns.

Word	Noun	Adjective	Verb	Adverb
Ygdrasil	Yes	No	No	No
Yggdrasil	Yes	No	No	No

As nouns, Ygdrasil and Yggdrasil are synonyms defined as:

Ygdrasil and Yggdrasil: (Norse mythology) a huge ash tree whose roots and branches hold the earth and Heaven and Hell together

Ygdrasil (noun)	Yggdrasil (noun)
(Norse mythology) a huge ash tree whose roots and branches hold the earth and Heaven and Hell together	(Norse mythology) a huge ash tree whose roots and branches hold the earth and Heaven and Hell together