[pinkpanther]

We say "Rabbana" (our Lord) or "Rabbi" (my Lord) many many times in our daily prayers. From that two transliteration, you can gather that Rabb means Lord.

It is possible that Jesus actually said "Rabb" instead of "Abb". Why is it possible? Because of embellishment which is replete in the Gospels.

I think satan misled you on the first line that it should be "Rabb" not "Rabbi"
Rabbi is a Jewish scholar or teacher