Verb. A term originating from Long Beach, NY. The act of calling someone's name typically in a high falsetto voice in order for said someone to turn around quickly, and hence, break their neck.
Mike: *falsetto voice* "EXCUSE ME, JAMIE!??!"
Jamie: *turns around in confusion, breaking neck*
When you absolutely care about someone enough to do anything for them even when they don't want or need your help you broke your neck for them or looking out for them when you know they need someone to care for them
You really going to choose her over me when I was the onebreaking my neck for you