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Synonyms for PR (same or very similar meaning)

WordNet sense 1 (a soft yellowish-white trivalent metallic element of the rare earth group; can be recovered from bastnasite or monazite by an ion-exchange process):

WordNet sense 2 (a self-governing commonwealth associated with the United States occupying the island of Puerto Rico):
Puerto Rico, Commonwealth of Puerto Rico, Porto Rico

WordNet sense 3 (a promotion intended to create goodwill for a person or institution):
public relations

From the ODE community, based on WordNetadd/edit