Concise Bible Dictionary:
Besides the ordinary use of the word in its literal sense, it is applied to cousins and nephews (Gen. 14:14; Lev. 10:4); and to kinsmen generally (Ex. 2:11; 2 Kings 10:13; 2 Chron. 22:8). Also employed where there is a moral likeness (Job 30:29; Prov. 18:9). See BRETHREN.
Strong’s Dictionary of Hebrew Words:
Meaning:
from (the orig. of) 2992; a brother-in-law
KJV Usage:
husband's brother