B with flourish

B with flourish (Ꞗ, ꞗ) is the modern name for the third letter of the Middle Vietnamese alphabet, sorted between B and C. The B with flourish has a rounded hook that starts halfway up the stem (where the top of the bowl meets the ascender) and curves about 180 degrees counterclockwise, ending below the bottom-left corner. It represents the voiced bilabial fricative /β/, which in modern Vietnamese merged with the voiced labiodental fricative, written as the letter V in the Vietnamese alphabet. (In Middle Vietnamese, V represented the labio-velar approximant /w/.)

The B with flourish is known principally from the works of Jesuit missionary Alexandre de Rhodes, particularly his trilingual dictionary Dictionarium Annamiticum Lusitanum et Latinum (1651) and bilingual Cathechismus (1658). For example, vậy was written ꞗệy. As with the letter Đ, only the lowercase form ꞗ is seen in these works, even where a capital letter would be expected.

The Vietnamese alphabet was formally described for the first time in the 17th-century text Manuductio ad Linguam Tunckinensem, attributed to a Portuguese Jesuit missionary, possibly Francisco de Pina or Filipe Sibin. This passage about the letter Ꞗ was later incorporated into de Rhodes's Dictionarium:

The passage roughly translates to:

Although some peculiarities of de Rhodes's orthography persisted into the early 19th century, the B with flourish had by then become V, as seen in the writings of Vietnamese Jesuit Philipphê Bỉnh (Philiphê do Rosario).

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