Sukun is a term used in the Arabic language that refers to a diacritical mark, specifically a small symbol placed above a consonant. It indicates that the consonant is not followed by a vowel sound, effectively showing that the syllable is closed. This mark is essential for proper pronunciation and understanding of Arabic words. In the context of Arabic script, the use of sukun helps learners and speakers distinguish between words that may look similar but have different meanings based on vowel sounds. Understanding sukun is crucial for reading and writing in Arabic, as it contributes to the clarity of communication in the language.