The Hebrew Rabbi By Dr. Eli Lizorkin-Eyzenberg
The term רַבִּי (rabbi) “my teacher” is ancient. Its original meaning translated from Hebrew literally means “one of abundance”. In Hebrew, oftentimes רַב (rav) is a measure relating to numerical quantity or length. The term רַב (rav) simply means “much”, “many”, “numerous” or “great.”
But with the addition of the letter י (yud) on the end, a suffix of possession, we can literally translate רַבִּי (rabbi) as “my great one”.