brother-in-law
cognati
koh-NYAH-toh
In Italian, cognato can be your spouse's brother, or the husband of your sibling. Context makes this clear. 'Cognati' (plural) is used for all brothers-in-law or mixed groups of in-law siblings.
Mio cognato è il fratello di mia moglie.
My brother-in-law is my wife's brother.
Il cognato è venuto ad aiutarmi a fare i traslochi.
My brother-in-law came to help me with the move.