To Queer

1. (transitive, dated) To render an endeavor or agreement ineffective or null.

Synonym: invalidate

2. (Britain, dialect, dated) To puzzle.
3. (slang, dated) To ridicule; to banter; to rally.
4. (slang, dated) To spoil the effect or success of, as by ridicule; to throw a wet blanket on; to spoil.
5. (social sciences) To reevaluate or reinterpret (a work) with an eye to sexual orientation and/or to gender, as by applying queer theory.