Acarya / Acharya
“Teacher ormaster. Applied to an eminent priest who guides the student in conduct and sets an example for him.”
“One of the two kinds of spiritual leaders known in Buddhism; the second type of teacher is the upadhyaya.
Originally acharya was understood to mean a master of the Dharma, whereas the upadhyaya taught discipline and adherence to the rules.”
See also: Ajahn.