expanse vs footprint

expanse and footprint both are nouns.

Word	Noun	Adjective	Verb	Adverb
expanse	Yes	No	No	No
footprint	Yes	No	No	No

As nouns, footprint is a hyponym of expanse; that is, footprint is a word with a more specific, narrower meaning than expanse:

Other hyponyms of expanse include acreage, land area, erasure, blank space, place, space, space, balk, baulk, plane section, section.

expanse (noun)	footprint (noun)
the extent of a 2-dimensional surface enclosed within a boundary	the area taken up by some object
a wide scope	a mark of a foot or shoe on a surface
a wide and open space or area as of surface or land or sky	a trace suggesting that something was once present or felt or otherwise important