Refers to one's own older brother. When addressing or referring to someone else's older brother, お兄さん is more polite.
See also: 弟
My older brother lives in Tokyo.
兄と一緒に映画を見に行った。
I went to see a movie with my older brother.
Specifically an older brother-in-law: either the spouse's older brother or the older sister's husband. Compare 義兄, which is more explicit.
See also: 義兄
兄は姉の夫で、とても優しい人です。
My brother-in-law is my older sister's husband, and he is a very kind person.
I have one older brother.
He looks like his older brother.
I get along well with my older brother.
elder brother; one's senior · dashing young man; gallant young lad
older brother (honorific)