Sonia Sikka in a note on Shankaracharya refers to him as an 8th.C. philosopher and theologian.
I don’t think I’m being captious when I offer the criticism that this is a reduction to Western ‘forms of life’ of the great acharya. Why not immediately call him that or hasten to qualify? Hidden in that description is the sense that being a teacher is a lesser role than philosopher or theologian. As one progresses in those professions one expects to have less to do with the 101 classes and the great luminaries hardly teach at all. What the average student remembers is the teachers that he has encountered and for the culture at large they are the most important members of the profession and not the purveyors of papers hardly ever read even by their peers.
Wikipedia has a definition:
The term "acharya" is most often said to include the root "char" or "charya" (conduct). Thus it literally connotes "one who teaches by conduct (example)," i.e. an exemplar. (citation needed)
By the way that ‘citation needed’ a favorite Wiki sprinkle is fatuous. When you’ve given the etymology presumably from a Sanskrit dictionary then what more certification do you need. Is there a dispute? If I wrote ‘domicile’ originally from ‘domus’(Lat.) a home must I cite ‘White’s Latin Dictionary’ as a source. Now I’m getting captious.