U+A704 "꜄" Modifier Letter Chinese Tone Yin Qu Unicode Character

U+A704 "꜄" Modifier Letter Chinese Tone Yin Qu is a specialized diacritic mark used in linguistic transcription systems for Chinese languages, specifically representing the fourth tone in the traditional four tone classification of Middle Chinese, known as the "departing tone" or "去声." In the Yin Qu category, this tone is characterized as a high falling pitch contour, and the modifier letter form (as opposed to a full tone letter) is intended to be attached to a preceding character to indicate this tonal annotation, often appearing in scholarly works on historical Chinese phonology or in descriptions of tone sandhi patterns.