Siddham Letter U

It writes the independent vowel u at the start of a Siddham syllable. 𑖄 is the independent Siddham letter for Sanskrit u. If u follows a consonant, Siddham writes it with a vowel sign attached to that consonant. The independent letter and the dependent u sign are not interchangeable.

Siddham developed in South Asia around the 5th century within the Brahmi-derived script tradition. North Indian records called related forms Siddhamātr̥kā or Kuṭila in the 6th–10th centuries. Siddham is most closely related to Śāradā, and its script family contributed to later Nāgarī forms.

Why does it appear in Buddhist writing?

Siddham was used to write Sanskrit, including Buddhist texts. It reached China around the 6th–7th centuries and later Korea and Japan. In 806, the Japanese monk Kūkai returned from Tang China with Sanskrit study materials and Siddham texts, helping establish the tradition in Japan.

As of 2026, its strongest surviving use is ritual and ceremonial writing in Japanese Shingon and Tendai Buddhism. In Japanese, Siddham characters are also called bonji.

What does it mean when someone sends it?

By itself, it is usually a letter sample, not a full message. With a script chart, read it as the initial u; in an inscription, the surrounding words and tradition help explain its role.

In Japanese esoteric Buddhist practice, some individual Siddham characters can work as phonetic syllables or represent Buddhist deities. That does not identify a deity for 𑖄 by sight: its letter value is u. Treat an isolated character as a letter unless the inscription supplies a ritual reading.