pronoun
you (honorific, familiar, male)
Honorific second-person pronoun used mainly by men in letters to address a male friend or superior. Familiar yet respectful; not used in everyday speech.
拝啓 兄におかれましては、ますますご清栄のこととお喜び申し上げます。
Dear Sir, I hope this letter finds you in ever greater prosperity.
suffix
Mr.; Mister (honorific suffix in letters)
Honorific suffix attached to the name of a male friend or superior in letters, similar to 'Mr.' but more intimate and respectful. Used by men.
山田兄、先日はありがとうございました。
Dear Mr. Yamada, thank you for the other day.
noun
Original meaning; now archaic or literary. In modern Japanese, 兄 is normally read あに for 'older brother'.
See also: 兄 (あに)
古語では「けい」は兄を指したが、現代では「あに」が一般的である。
In classical language, けい meant older brother, but today あに is common.