兄|あにani[1]atamadaka (head-high)

1. nounolder brother; elder brother
   私の兄あには技師ぎしになった。↗

   My brother became an engineer.
2. nounbrother-in-law (spouse's older brother or older sister's husband)

• Synonym兄貴あにきCasualColloquial and affectionate; also a big-brother figure in the yakuza or among craftsmen. Used mainly by men.
• Synonym兄ちゃんにいちゃんCasualAn affectionate pet name for one's own brother; also a casual way to address a young man, as in 「そこの兄ちゃん」.
• Synonym兄さんにいさんNeutralUsed to address your brother directly, and also young men you don't know; when mentioning your brother to others, use 「兄」.
• Related兄者あにじゃWrittenAn archaic term for one's brother, heard mostly in period dramas; today it appears occasionally in mock-archaic or joking speech.
• Related兄御あにごFormalA formal, old-fashioned honorific for another person's older brother; in modern speech people say 「お兄さん」.
• Related大兄たいけいWrittenIn letters, an honorific used by men for an older friend or senior; it can also serve as a second-person pronoun.
• Related兄いあにいCasualSlangy: an older man, or a dashing guy with a streetwise air; carries the flavor of old downtown Tokyo (shitamachi).
• Related兄様にいさまFormalA respectful form of address, found mainly in upper-class families or in novels; rarely used in daily conversation.
• Antonym弟おとうとNeutralThe opposite of 「兄」: a male sibling younger than oneself.

Use 「兄」 when mentioning your older brother to outsiders; address him directly as 「お兄さん」 or 「兄ちゃん」. 「兄貴」 adds affection or a streetwise tone, and 「弟」 means younger brother.

Usage comparisons are AI-assisted and cross-checked by multiple models; for study reference only

1. （あに）同おなじ親おやから生うまれた年上としうえの男おとこ。