Here are some synonyms for "reticent":
* Reserved
* Shy
* Withdrawn
* Quiet
* Taciturn
* Uncommunicative
* Close-mouthed
Here's an example of how "reticent" can be used in a sentence:
"Despite her success, the famous actress remained reticent about her personal life."
In this example, the sentence means that the actress didn't like to talk about her personal life, even though she was a famous person.