IMAM MUBIN امام مبين
“The clear prototype or model.” The expression occurs twice in the Qur’an, Surah xxxvi. 11. “Everyone we do set down in a clear prototype (f i Lmamin Mubinin). Here it appears to be used for the Qur’an as an inspired record. Surah xv. 79, “Verily they became both, Sodom and Midian, a clear example.” (labi Imamin Muhinin). Muslim teachers use the word for the Lahsau ‘l-Mahfuz or the Tablet of Decrees.
Based on Hughes, Dictionary of Islam