What was the field bought with Judas's reward called in the local language?

Answer: Akeldama

The people of Jerusalem called it Akeldama (KJV: Aceldama), which means Field of Blood.

“(Now with the reward for his wickedness Judas bought a field; there he fell headlong and burst open in the middle, and all his intestines spilled out. This became known to all who lived in Jerusalem, so they called that field in their own language Akeldama, that is, Field of Blood.)”— Acts 1:18-19 (BSB)