U+1D154 "𝅔" Musical Symbol Triangle-Round Notehead down White Unicode Character

U+1D154 "𝅔" Musical Symbol Triangle-Round Notehead down White is a notation element used in Western musical scores from the medieval and Renaissance periods, particularly within mensural notation, where it represents a specific rhythmic value classified as a semibrevis or half breve. Its shape combines a triangular form merging into a rounded base, oriented with the tip pointing downward and filled with white or hollow ink, which distinguishes it from other filled or upward-pointing variants. This sign was historically employed to denote a note of moderate duration, fitting into the complex proportional timing systems of early polyphonic music before the standardization of modern notehead shapes.