digamma

 
Pronunciation: /dʌɪˈgamə/

noun

  • the sixth letter of the early Greek alphabet (Ϝ, ϝ), probably pronounced as ‘w’. It became obsolete before the Classical period.

Origin:

late 17th century: via Latin from Greek, from di- 'twice' + gamma (because of the shape of the letter, resembling gamma (Γ) with an extra stroke)