U+01B0 "ư" Latin Small Letter U with Horn Unicode Character

U+01B0 "ư" Latin Small Letter U with Horn is a distinct grapheme used primarily in the Vietnamese alphabet, where it represents a high back unrounded vowel sound that differs from the standard "u" by the addition of a small horn-like diacritical mark attached to the upper right of the letter. This character is essential for accurately writing and distinguishing words in Vietnamese, such as "tư" meaning four or thought, from words using a plain "u." It belongs to the Latin Extended-B block of Unicode and is often encountered in tonal notations where it can combine with various tone marks.