'Sister in law' in the Bible

But and if the man will not take his sister-in-law, then let her go to the gate unto the elders and say, 'My brother-in-law refuseth to stir up unto his brother a name in Israel, he will not marry me.'

then let his sister-in-law go unto him in the presence of the elders and loose his shoe off his foot and spit in his face and answer and say, 'So shall it be done unto that man that will not build his brother's house.'

Then she said, "See, thy sister-in-law is gone back again unto her people and unto her god: return thou after her."