Admittedly Quran is the main source of divine guidance for humanity. The scholars of Arabic Language had tremendous efforts to discover the exact meanings of the words used in the Holy Quran as to comprehend the essence of Quranic guidance. Explanation of Odd words (Ghrab-ul-Quran) is one of the most important branch of Arabic Lexicography. Al-amam Raghib al-Asfahni (D. 502 A.H.), his book (Al-Mufirdat-fi-Ghareeb-ul-Quran) occupies an important place in this particular branch of Islamic exegeses. Its importance, authenticity and authority can be visualized by the survey of Tafseeri Literature produced during the last many centuries which is replete with the quotations and references from the book of Amam Raghib. The article deals with the biography of Amam Raghib and some salient features of his book (Al-Mufirdat-fi-Ghareeb-ul-Quran). The book is of paramount importance with reference to understanding the quranic odd words.