Ramat Gan.
RamAllah.
Rimmon.
Hiram (Ahiram).
Yehoram.

Rabbi as “my master” is good etymology and a good description. That Judaism expects one who knows more to teach others is logical, but not linguistically historical.

“Moreh” or “Morah” (male or female) means teacher.

I’ll have to agree with the others. The historic and most literal translation would be “master”. A less literal, but probably more accurate translation (reflecting the need for ordination in order to be a rabbi) might be “doctor” (in the PhD sense of the word.)

Translating “rabbi” as “teacher” is like calling everybody with a PhD “professor”.

The answer to your question really depends on what you want to do with it.

“Rabbi” (pronounced “rah-bee” in Hebrew) literally means “my master.” It comes from the word “rav,” whch means “master.” When we lead the Grace after Meals, we say “Rabbotai, nevarekh” — “My masters, let us recite the blessing.” In modern Hebrew, “rabbotai” is the equivalent of “gentlemen.” On airplanes or in theaters, one frequently hears announcements begin with the phrase: “Gevirotai ve-rabbotai…” which is simply “Ladies and gentlemen.”

One example of usage from Talmudic times: There is a saying in the Talmud, “Kanah eved, kanah rabbo” — “One who buys a slave buys his own master.” This was because owners were under such strong obligations to treat their slaves well that a slave might actually be considered his owner’s master in some ways.

Now that I think about it, “rav” seems to me to have much the same connotations as the word “master” does today: a revered teacher or simply a free, independent individual.