Porto Rico vs PR

Porto Rico and PR both are nouns.

Word	Noun	Adjective	Verb	Adverb
Porto Rico	Yes	No	No	No
PR	Yes	No	No	No

As nouns, Porto Rico and PR are synonyms defined as:

Porto Rico and PR: a self-governing commonwealth associated with the United States occupying the island of Puerto Rico

Other synonyms of Porto Rico include Commonwealth of Puerto Rico, Puerto Rico.

Porto Rico (noun)	PR (noun)
a self-governing commonwealth associated with the United States occupying the island of Puerto Rico	a promotion intended to create goodwill for a person or institution
the smallest and easternmost of the Greater Antilles in the Caribbean	a self-governing commonwealth associated with the United States occupying the island of Puerto Rico