embellishment vs decoration

embellishment and decoration both are nouns.

Word	Noun	Adjective	Verb	Adverb
embellishment	Yes	No	No	No
decoration	Yes	No	No	No

As nouns, decoration is a hypernym of embellishment; that is, decoration is a word with a broader meaning than embellishment:

embellishment: the act of adding extraneous decorations to something
decoration: the act of decorating something (in the hope of making it more attractive)

As nouns, decoration is a hypernym of embellishment; that is, decoration is a word with a broader meaning than embellishment:

Other hypernyms of embellishment include ornament, ornamentation.

embellishment (noun)	decoration (noun)
the act of adding extraneous decorations to something	the act of decorating something (in the hope of making it more attractive)
a superfluous ornament	something used to beautify
elaboration of an interpretation by the use of decorative (sometimes fictitious) detail	an award for winning a championship or commemorating some other event