keepsake vs physical object

keepsake and physical object both are nouns.

Word	Noun	Adjective	Verb	Adverb
keepsake	Yes	No	No	No
physical object	Yes	No	No	No

As nouns, physical object is a hypernym of keepsake; that is, physical object is a word with a broader meaning than keepsake:

keepsake: something of sentimental value
physical object: a tangible and visible entity; an entity that can cast a shadow

Other hypernyms of keepsake include object.

keepsake (noun)	physical object (noun)
something of sentimental value	a tangible and visible entity; an entity that can cast a shadow