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- Meforshim Nick"names 3 answers
Rashi, Rambam, the Maharal, the Rosh, the Rema, etc. are all usually referred to by their acronyms. This custom makes sense in a culture that is mostly transmitted through the written word where ink and paper were not cheap - someone wrote רש"י, so I say Rashi.
Who was the first person to be generally addressed as an acronym? Who popularized the use of that acronym?