1.(noun) A Jewish-looking doofus.
2.(noun) A doofus with an extremely largenose.
"Marty stopped by my cubicle this afternoon. Corporate should move that jewfus from mergers to accounting. I bet his shylock nose can smell a dime from a mile away."
I think the most logical explanation for "Jewsus" is Jesus, as we know him today, before he went Christian. I mean, "Jew" for Jewish, and "Jesus" for "Sus". With me?
"I wonder what Jesus was called when he was still Jewish..."
"I know! Jewsus!!!"
"That's quite comical."