Sister-In-Law

see also PITA
a) the female sibling of a person's husband or wife.
b) a troublemaking sibling of your wife who spends all waking moments trying to cause trouble between you and your wife.
c) (WVA only), see Aunt Gladys.

My sister-in-law, Danielle, kept encouraging my wife to dump me.

by ADubbs July 01, 2005