public utility company vs public-service corporation

public utility company and public-service corporation both are nouns.

Word	Noun	Adjective	Verb	Adverb
public utility company	Yes	No	No	No
public-service corporation	Yes	No	No	No

As nouns, public utility company and public-service corporation are synonyms defined as:

public utility company and public-service corporation: a company that performs a public service; subject to government regulation

Other synonyms of public utility company include public utility, utility.

public utility company (noun)	public-service corporation (noun)
a company that performs a public service; subject to government regulation	a company that performs a public service; subject to government regulation