Is macdonalds common or proper noun?

The noun MacDonalds (plural) or MacDonald's (possessive) is a proper noun, the name of a specific company or a specific person or family. A proper noun is always capitalized.

A common noun is a general Word for any person, place, or thing. Examples of common nouns for the plural noun MacDonalds is brothers, sisters, or family. Examples of common nouns for the possessive noun MacDonald's is company, store, or chain.