U+01D9 "Ǚ" Latin Capital Letter U with Diaeresis and Caron Unicode Character

U+01D9 "Ǚ" Latin Capital Letter U with Diaeresis and Caron is a composite glyph used primarily in certain romanization systems and specialized orthographies, such as in the Pinyin romanization of Mandarin Chinese for specific phonological distinctions where it represents a high front rounded vowel with a rising tone. The diaeresis (two dots above the letter) modifies the base vowel sound, while the caron (a small v-shaped diacritic above the dots) indicates a specific tonal contour, typically the third or falling-rising tone in linguistic contexts. This character is rare in everyday writing and is more commonly encountered in linguistic notation, academic texts, or dictionaries where precise tonal and vowel representation is required.