Translation guide
In Japanese, how you refer to your brother depends on whether he is older or younger, the level of formality, and whether you are talking about your own brother or someone else's. There is no single word that covers all uses of 'brother'.
Referring to your own older brother in casual conversation, such as with family or friends.
The standard word for your own older brother when speaking to others. Not used to address him directly.
My older brother is a college student.
Affectionate term used to address your own older brother directly, or to refer to him within the family. Often used by children.
お兄ちゃん、遊ぼう！
Big brother, let's play!
Rough or slangy term for one's own older brother, often used by males. Can also mean a senior in a gang or group.
兄貴、それかっこいいね。
Bro, that's cool.
Referring to someone else's older brother politely, or in formal situations.
Polite term for someone else's older brother. Also used to address a young man politely.
田中さんのお兄さんは医者ですか。
Is Tanaka's older brother a doctor?
Very formal and respectful term for one's own older brother, used in traditional or samurai contexts.
Referring to your own younger brother in casual conversation.
The standard word for your own younger brother when speaking to others. Not used to address him directly.
弟はまだ高校生です。
My younger brother is still in high school.
Referring to someone else's younger brother politely.
Polite term for someone else's younger brother.
弟さんはおいくつですか。
How old is your younger brother?
Referring to brothers collectively, or siblings in general.
Means 'brothers' or 'siblings' (can include sisters). Used for both your own and others' siblings.
兄弟が三人います。
I have three siblings.
Polite form of 兄弟, used when referring to someone else's siblings.
ご兄弟は何人ですか。
How many siblings do you have?
Calling your brother by name or title in conversation.
Japanese speakers typically address their own brothers by name (with or without honorifics) or by family role terms like お兄ちゃん (for older) or just by name for younger. Using 兄 or 弟 directly to address them is unnatural.
太郎、ちょっと来て。
Taro, come here a moment.
お兄ちゃん、それ取って。
Big brother, get that for me.
Words like 兄 (ani) and 弟 (otōto) are used to refer to your brother when talking about him to others. They are not used as direct forms of address. To call your brother, use his name or a family term like お兄ちゃん.
兄 (ani) is humble and used for your own older brother. お兄さん (onīsan) is polite and used for someone else's older brother or to address a young man. Using お兄さん for your own brother to outsiders sounds childish or overly familiar.
Elder brother, I am relieved you are safe.