Final answer:
A possessive noun is a noun that shows ownership or relationship between two things. An apostrophe is used to indicate possession.
Step-by-step explanation:
A possessive noun is a noun that possesses, or owns something in the sentence. It shows ownership or relationship between two things in the sentence. An apostrophe (') is used to indicate possession.
 Examples:
 - John's car
  - The dog's bone
  - The students' books
  
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