* A misspelling of a real name, such as Rihanna, Rayanna, or Rhiana.
* A made-up name. Some people create unique names for their children.
* A name specific to a certain culture or language that is not widely known.
To find the meaning, you would need more context:
* Where did you encounter this name?
* Is there any other information about the name, like its origin or usage?
Without more information, it's impossible to determine the meaning of "Rhayanna."