land mass vs New World

land mass and New World both are nouns.

Word	Noun	Adjective	Verb	Adverb
land mass	Yes	No	No	No
New World	Yes	No	No	No

As nouns, New World is a hyponym of land mass; that is, New World is a word with a more specific, narrower meaning than land mass:

land mass: a large continuous extent of land
New World: a country or continent discovered or colonised by European explorers from the sixteenth century onwards

Other hyponyms of land mass include continent, subcontinent.

land mass (noun)	New World (noun)
a large continuous extent of land	a country or continent discovered or colonised by European explorers from the sixteenth century onwards