Apostrophe/əˈpɑːstrəfi/ Definition 1 of 2Pro Tip 1/3Shows Possession An apostrophe can indicate that something belongs to someone or something. That is Maria's car. Pro Tip 2/3Indicates Omissions Use an apostrophe in contractions where letters or numbers are omitted. She'll go to the party instead of She will. Pro Tip 3/3Plural Confusion Remember, don't use an apostrophe to make regular nouns plural. Incorrect: Apple's for sale. Correct: Apples for sale.