Orig: a primitive root of doubtful meaning; used only as a denominative from 2993; to marry a (deceased) brother's widow:--perform the duty of a husband's brother, marry. H2993
1) (Piel) to perform levirate marriage, perform the duty of a brother-in-law 1a) the duty due to a brother who died childless - to marry his widow and have a son for his name