land site vs parcel of land

land site and parcel of land both are nouns.

Word	Noun	Adjective	Verb	Adverb
land site	Yes	No	No	No
parcel of land	Yes	No	No	No

As nouns, parcel of land is a hypernym of land site; that is, parcel of land is a word with a broader meaning than land site:

land site: the piece of land on which something is located (or is to be located)
parcel of land: an extended area of land

Other hypernyms of land site include parcel, piece of ground, piece of land, tract.

land site (noun)	parcel of land (noun)
the piece of land on which something is located (or is to be located)	an extended area of land