English

Noun

deal breaker ‎(plural deal breakers)

1. (idiomatic) An issue which causes a relationship (especially in business) to fail.
   • 2004 -- Mark A. Williams: Your Identity Zones: Who Am I? Who Are You? How Do We Get Along?, page 294:

     Sometimes the process of digging uncovered a deal breaker.

See also

• last straw
• showstopper