English edit

Alternative forms edit

Etymology edit

From Middle English breþeren in lawe, equivalent to brethren +‎ in +‎ law.

Noun edit

brethren-in-law

  1. (archaic) plural of brother-in-law
    • 1997, David A. Chappell, Double Ghosts: Oceanian Voyagers on Euroamerican Ships, page 60:
      And if, occasionally, their superior position made these officers in times of emergency address their tattooed brethren-in-law in vigorous and uncomplimentary language, emphasized by a knockdown blow, no ill will was either felt on one side nor engendered on the other.