Al-Mufradat fi Gharib al-Quran (Arabic: المفردات في غريب القرآن) is a classical dictionary of Qur'anic terms by 11th-century Sunni Islamic scholar Al-Raghib al-Isfahani. It is widely considered by Muslims to hold the first place among works of Arabic lexicography in regard to the Qur'an. [Wikipedia]
This is the Arabic version. I intend to translate it in the (near) future and publish it here as well, to make it easy for non-Arabic learners, إن شاء الله