Onii-san is the honorific while the actual word is ani.
兄 (ani) is older brother in Japanese. When addressing someone else's older brother, you should use お兄さん (onii-san).
Otouto is younger brother, ani is older brother.
Nii-chan or Nii- nii is Japanese for older brother. Onii-chan is someone else's older brother.
Arigato, Onii-san or Arigato, Onii-sama. Depending on the relationship between the brother and sibling, the honorific suffix can change. San is an honorific for those not very close but not very distant either. If the person respects their brother very highly, it would be Onii-sama. Hope that helps.
Very respectful older brother.
Nii-chan means "older brother" in Japanese.
older brother=oniisan younger brother=otooto
It can be translated as 'older brother.'
사마
The honorific 'chan' is written asちゃん in Japanese.
You may say 'ani' for older brother, and 'otouto' for younger brother, written (in that order): 兄 弟
A Term for an older brother or someone honored.