Wiktionary
yeshivish
a. 1 Relating to a yeshiva. 2 Relating to the culture of Haredi Jews.
Wikipedia
Yeshivish
Yeshivish , also known as Yeshiva English or "Yeshivisheh Shprach," is a sociolect of English spoken by Yeshiva students and other Jews with a strong connection to the Orthodox Yeshiva world.