What is "nixed"

Usage examples of "nixed".

He said he developed a theory to explain why the Outfit nixed the hit.

He thought of Albanese as the killer--a phony car theft reported--and nixed the idea as farfetched.

Buzz thought of cash shakedowns--him against fences and hotel crawlers he’d leaned on as a cop, then nixed the notion--he’d gotten older and flabbier, while they’d probably gotten meaner and better armed.