Ani (兄) means "my older brother." You use this term when referring to your own older brother while speaking to someone who is not part of your family. For addressing your older brother directly, or when talking about someone else's older brother, use "oniisan" (お兄さん). Example: 私の兄は大学生です。(Watashi no ani wa daigakusei desu.) = My older brother is a university student.

自分の兄を、家族以外の人に話す時に使います。例：私の兄は大学生です。