However, it's important to note that "onee" is a Japanese word, and the spelling and pronunciation can vary depending on the context and dialect.
Here's a breakdown of its usage:
* "Onee-chan" is the most common way to write it, meaning "older sister" in Japanese.
* "Onee-san" is a more formal way to address an older sister.
It's always best to check the context or consult a Japanese dictionary for the most accurate spelling.