Also 5 brodyr yn lawe, broder in law, broder elawe. [App. ‘in law’ = in Canon Law (in contrast to brother in blood or by nature), with reference to the degrees of affinity within which marriage is prohibited; a brother-in-law or sister-in-law being, as regards intermarriage, treated ‘in law’ as a brother or sister.]
prop. The brother of one’s husband or wife; the husband of one’s sister. Sometimes extended to the husband of one’s wife’s (or husband’s) sister.
c. 1300. K. Alis., 4399. He was Daries brother in lawe.
[c. 1425. Voc., in Wr.-Wülcker, 672. Hic leuir, est frater in lege.]
1483. Cath. Angl., 45. A Broder in law [v.r. Broder elawe], leuir.
1522. Bury Wills (1850), 117. I bequethe to John Bullok, my brother in law, a fetherbed.
1552. Huloet, Brotherne by mariynge the doughters of one man, called brothern in lawe.
1596. Shaks., 1 Hen. IV., I. iii. 80. That we at our owne charge, shall ransome straight His Brother-in-Law.
1700. Tyrrell, Hist. Eng., II. 901. On his Brother-in-Law’s behalf.
1830. Miss Mitford, Village, Ser. IV. (1863), 273. Oakhampstead Park, the pleasant demesne of her brother-in-law, Sir Arthur Villars.
† b. humorously. The father of one’s daughter-in-law or son-in-law. Obs.
1611. Shaks., Wint. T., IV. iv. 720. Who … is no honest man to goe about to make me the Kings Brother in Law.
Hence Brother-in-lawship.
1840. Thackeray, Paris Sk. Bk. (1885), 98. The pleasures of brother-in-lawship in general.
