お兄さん（おにいさん、oniisan）
- older brother

The Japanese word お兄さん is a polite term for "older brother". It's a respectful way to address or refer to someone who is older than you and male. The "お" at the beginning is a polite prefix, and "兄さん" (にいさん) itself means "older brother". It expresses respect and warmth. It is used more often than the more formal 兄 (あに).

⚫︎お兄さんはかっこいいですね！ Translation: Your older brother is cool, isn't he! ⚫︎お兄さんの車は速い。 Translation: My older brother's car is fast. ⚫︎すみません、お兄さんはいますか？ Translation: Excuse me, is your older brother here?

⚫︎You can use お兄さん to directly address your own older brother. ⚫︎You can also use it to address or refer to other people's older brothers. ⚫︎It's generally used when speaking politely or respectfully, especially to someone older than you. ⚫︎お兄さん is common in daily conversation, and is used when you are not especially familiar with someone or when you wish to show deference. ⚫︎The level of politeness is not extremely high, so it’s acceptable in various situations.

⚫︎The word is typically written in hiragana as お兄さん. ⚫︎You can also write it with kanji and hiragana: お兄さん. ⚫︎The kanji for 兄 means "older brother". ⚫︎There are no variations in okurigana (the suffix hiragana).

⚫︎兄 (あに): More formal term for "older brother." ⚫︎兄貴(あにき): A slightly less formal and sometimes more affectionate term, similar to "bro" or "big brother" in English.

⚫︎弟(おとうと): Younger brother. ⚫︎妹(いもうと): Younger sister. ⚫︎姉(あね): Older sister.

私のお兄さんはとても親切です。 ・Translation: My older brother is very kind. ・Explanation: This sentence describes the speaker's own older brother using the term お兄さん.

すみません、田中さんのお兄さんはどちらですか？ ・Translation: Excuse me, which one is Mr. Tanaka's older brother? ・Explanation: This sentence uses お兄さん when asking about someone else's older brother.

The word is formed by adding the honorific prefix "お" to "兄さん" (にいさん). "兄" (あに) itself comes from Old Japanese. The "さん" is a respectful suffix added to names and roles in Japanese, used to show familiarity and respect to someone close to you. The prefix "お" is an honorific prefix used to show respect to the person being talked about.