A brother is a male sibling. In English, there are two types of siblings – a full brother and a half brother. In a familial relationship, the term “brother” typically refers to a first-degree relative. However, in some cases, the term “sister” is also used.
A brother is a male descendant of the same parents as you, and a half-brother is a male of the same sex. In other cultures, a brother and a half-brother can be of different sex. In the modern world, a brother and a half-sister are the same gender, but their biological relationship is different.
In English, the word brother comes from Middle English, which is a shortened form of the Old English word brothor. It is derived from Proto-Indo-European *bhreh2ter. It is also used in Irish, Russian, and Persian. Some dialects have their own forms of brother and half-brother, which can be difficult to tell apart.