look up any word, like trill:
 
1.
Spanish for "Brother-in-law"

It often is used as a taunt to a male with a sister, especially an attractive sister, basically implying that whoever is doing the name calling is having relations with the name receiver's "hot" sister.
Oye, ¿cómo estás cuñado, hermano de me novia?

"Hey, how are you 'cuñado', brother of my girlfriend?

En tus sueños, cabron, mi hermana no le gustan a los pinche mojados.

"In your dreams, bastard, my sister doesn't like goddamn wetbacks."
by Claro October 03, 2007