discard vs physical object

discard and physical object both are nouns.

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

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

discard: anything that is cast aside or discarded
physical object: a tangible and visible entity; an entity that can cast a shadow

Other hypernyms of discard include object.

discard (noun)	physical object (noun)
getting rid of something that is regarded as useless or undesirable	a tangible and visible entity; an entity that can cast a shadow
(cards) the act of throwing out a useless card or of failing to follow suit
anything that is cast aside or discarded

discard (verb)	physical object (verb)
throw or cast away