ἀδελφός

Noun: ἀδελφός (adelphos), GK G81 (S G80) 343x. adelphos (“brother”) has a wide range of uses in the NT; a closely related word (adelphē) means “sister.” It denotes first of all a sibling from the same parents (Mt. 1:2, 11; 4:18, 21). adelphos can also refer to a fellow member or an associate of a person such as one who shares a belief system (Mt. 12:50). Since both men and women were involved in the early church, we should usually understand the plural of adelphos as “brothers and sisters.” adelphos can also indicate a person’s ethnic relationship, and is sometimes used in the simple sense of neighbor (Mt. 5:22).