Idgham with ghunnah is a rule in Tajweed, the art of reciting the Quran. It occurs when a letter from the group of noon saakin or tanween is followed by one of the letters of Idgham, specifically ya, waw, ra, or lam. In this case, the noon sound is merged into the following letter, creating a smooth transition. The term "ghunnah" refers to a nasal sound that is produced during this merging. It is essential to maintain this nasal quality for about two counts, ensuring clarity and proper pronunciation. This rule enhances the beauty and rhythm of Quranic recitation.