plate tectonics vs plate tectonic theory

plate tectonics and plate tectonic theory both are nouns.

Word	Noun	Adjective	Verb	Adverb
plate tectonics	Yes	No	No	No
plate tectonic theory	Yes	No	No	No

As nouns, plate tectonics and plate tectonic theory are synonyms defined as:

plate tectonics and plate tectonic theory: the branch of geology studying the folding and faulting of the earth's crust

Other synonyms of plate tectonics include tectonics.

plate tectonics (noun)	plate tectonic theory (noun)
the branch of geology studying the folding and faulting of the earth's crust	the branch of geology studying the folding and faulting of the earth's crust