U+20E1 "⃡" Combining Left Right Arrow Above Unicode Character

U+20E1 "⃡" Combining Left Right Arrow Above is a combining diacritical mark that is placed over a preceding base character to form a composite glyph, most commonly used in linguistic notation to represent a bidirectional or bidirectional shifting articulation, such as in phonetics for a sound that involves movement or interaction between two points, often appearing over a letter to indicate a prosodic or articulatory feature like a level tone or a floating tone in tonal languages, or to denote a harmonic relationship in some writing systems.