proximity vs nearness

proximity and nearness both are nouns.

Word	Noun	Adjective	Verb	Adverb
proximity	Yes	No	No	No
nearness	Yes	No	No	No

As nouns, nearness is a hypernym of proximity; that is, nearness is a word with a broader meaning than proximity:

Other hypernyms of proximity include closeness.

proximity (noun)	nearness (noun)
the property of being close together	the spatial property resulting from a relatively small distance
a Gestalt principle of organization holding that (other things being equal) objects or events that are near to one another (in space or time) are perceived as belonging together as a unit
the region close around a person or thing