oddity vs physical object

oddity and physical object both are nouns.

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

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

oddity: something unusual -- perhaps worthy of collecting
physical object: a tangible and visible entity; an entity that can cast a shadow

Other hypernyms of oddity include object.

oddity (noun)	physical object (noun)
something unusual -- perhaps worthy of collecting	a tangible and visible entity; an entity that can cast a shadow
a strange attitude or habit
eccentricity that is not easily explained