The term is a compound of the Hebrew words rosh ("head") and yeshiva (a school of religious Jewish education).
The rosh yeshiva is required to have a comprehensive knowledge of the Talmud and the ability to analyse and present new perspectives, called chidushim (novellae) verbally and often in print.
As a result, the role that a rosh yeshiva plays in Lithuanian Jewish communities is much more important than in the Hasidic ones.
Yeshivas continue the scholarly traditions of the sages of the Mishnah and Talmud who often headed academies with hundreds of students.
Regard for the rosh yeshiva in many ways is the transplantation of Hasidic attitudes in the Lithuanian world.
This concept, introduced by the Mussar movement in the 19th century, led to perfection of character as one of the aims of attending a yeshiva.