What's That in English?
If you know that cuñado means "brother-in-law" and cuñada means "sister-in-law" and that con means "with," you might be able to guess the meaning of concuñado/a: Your concuñado is the husband of your spouse's sister, and your concuñada is the wife of your spouse's brother. Got that?
As far as I know, English has no simple word or phrase to describe the same thing. But because the Spanish word might just come in handy, we've added it to our list of words for family relationships.


Comments
Just to round it up, in Mexico and some other Spanish speaking countries we use the word concuño instead of concuñado and concuña insteado of concuñada.
I’ve also heard consuegro/a to refer to people whose children are married, i.e. the parents of the bride as they relate to the parents of the groom.