What is "ramahurmuzi"

Abū Muḥammad al-Ḥasan ibn ʻAbd al-Raḥmān ibn Khallād al-Rāmahurmuzī (?—before 971 CE/360 AH), commonly referred to in medieval literature as Ibn al-Khallād, was a hadith specialist and author who wrote one of the first comprehensive books compiled in hadith terminology literature, al-Muḥaddith al-Fāṣil bayn al-Rāwī wa al-Wāʻī.