Purple Heart vs decoration

Purple Heart and decoration both are nouns.

Word	Noun	Adjective	Verb	Adverb
Purple Heart	Yes	No	No	No
decoration	Yes	No	No	No

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

Purple Heart: a United States military decoration awarded to any member of the armed forces who is wounded in action
decoration: an award for winning a championship or commemorating some other event

Other hypernyms of Purple Heart include laurel wreath, medal, medallion, palm, ribbon.

Purple Heart (noun)	decoration (noun)
a United States military decoration awarded to any member of the armed forces who is wounded in action	the act of decorating something (in the hope of making it more attractive)
	something used to beautify
	an award for winning a championship or commemorating some other event