publishing empire vs publishing conglomerate

publishing empire and publishing conglomerate both are nouns.

Word	Noun	Adjective	Verb	Adverb
publishing empire	Yes	No	No	No
publishing conglomerate	Yes	No	No	No

As nouns, publishing empire and publishing conglomerate are synonyms defined as:

publishing empire and publishing conglomerate: a conglomerate of publishing companies

publishing empire (noun)	publishing conglomerate (noun)
a conglomerate of publishing companies	a conglomerate of publishing companies