“Kenahora” is a curse in Yinglish (bastardized english/yiddish) world that comes from three words slurred together: the Yiddish word kein, meaning no,  ayin, which is Hebrew for eye, and hara, Hebrew for Evil. My informant’s mother would always say “don’t give us /it a kenahora” to mean “don’t give us bad luck.”
“If you are driving cross country let’s say, and making great time – but stupid decide to comment “Oh boy we are making great time” – BANG – you will instantly hit traffic – BUMPER TO BUMPER. It  always happens!” my informant tells me.

My informant’s grandmother also used to spit after saying Kenahora, “pu-pu-pu!” It implied spitting on the demon to stop it.