Ground Zero vs World Trade Center site

Ground Zero and World Trade Center site both are nouns.

Word	Noun	Adjective	Verb	Adverb
Ground Zero	Yes	No	No	No
World Trade Center site	Yes	No	No	No

As nouns, Ground Zero and World Trade Center site are synonyms defined as:

Ground Zero and World Trade Center site: the site of the World Trade Center before it was destroyed

Ground Zero (noun)	World Trade Center site (noun)
the site of the World Trade Center before it was destroyed	the site of the World Trade Center before it was destroyed