digamma

/daɪˈɡæmə/
noun
  1. An old letter of the Greek alphabet (Ϝ, ϝ) that represented a 'w' sound and was later dropped from the standard alphabet.
    • In some ancient inscriptions, the digamma appears where later texts have no letter.
    • The digamma was used in ancient Greek writing but is no longer part of the alphabet.
    • Scholars study the digamma to understand early Greek pronunciation.