御兄さん[oniisan] older brother
御兄ちゃん[oniichan] familiar form of "older brother"
御兄弟[gokyoudai] siblings
家兄[kakei] (my) elder brother
雅兄[gakei] polite word in letter to friend

義兄[gikei] brother-in-law
兄さん[niisan] older brother
兄嫁[aniyome] elder brother's wife
兄貴[aniki] one's senior

御兄弟[gokyoudai] siblings
愛弟子[manadeshi] favorite pupil
義弟[gitei] younger brother-in-law
兄弟[kyoudai] siblings
兄弟愛[kyoudaiai] brotherly love

兄弟子[anideshi] senior schoolmate
兄弟分[kyoudaibun] buddy
再従弟[saijuutei] younger second cousin
姉弟[shitei] older sister and younger brother
子弟[shitei] young(er) people