plutonic rock vs pluton

plutonic rock and pluton both are nouns.

Word	Noun	Adjective	Verb	Adverb
plutonic rock	Yes	No	No	No
pluton	Yes	No	No	No

As nouns, plutonic rock and pluton are synonyms defined as:

plutonic rock and pluton: large mass of intrusive igneous rock believed to have solidified deep within the earth

Other synonyms of plutonic rock include batholite, batholith.

plutonic rock (noun)	pluton (noun)
large mass of intrusive igneous rock believed to have solidified deep within the earth	large mass of intrusive igneous rock believed to have solidified deep within the earth