Zain is Hebrew for "a dick", Ain means "an eye", so literally it will be as in "a dick in one's eye", but is used for expressing a refusal or disappointment.
-Hey, can I borrow your jacket?
-Did you get those tickets?
-No, I've got Zain b'Ain
From Hebrew, literally means "A dick in an eye", this is actually a call of frustration when somthing bad has happened to you.
Tom was made a fool so he yelled "Zain B'ain"
phoneticlly "Za-yin Ba-a-yin"