myxoedema vs hypothyroidism

myxoedema and hypothyroidism both are nouns.

Word	Noun	Adjective	Verb	Adverb
myxoedema	Yes	No	No	No
hypothyroidism	Yes	No	No	No

As nouns, hypothyroidism is a hypernym of myxoedema; that is, hypothyroidism is a word with a broader meaning than myxoedema:

myxoedema: hypothyroidism marked by dry skin and swellings around lips and nose as well as mental deterioration
hypothyroidism: an underactive thyroid gland; a glandular disorder resulting from insufficient production of thyroid hormones

myxoedema (noun)	hypothyroidism (noun)
hypothyroidism marked by dry skin and swellings around lips and nose as well as mental deterioration	an underactive thyroid gland; a glandular disorder resulting from insufficient production of thyroid hormones