Nun is the fourteenth letter of the Semitic abjads, including Phoenician Nūn , Hebrew Nun נ, Aramaic Nun , Syriac Nūn ܢܢ, and Arabic Nūn ن (in abjadi order). Its numerical value is 50. It is the third letter in Thaana (ނ), pronounced as "nonou".
In all languages, it represents the alveolar nasal /n/.
The Phoenician letter gave rise to the Greek nu (Ν), Etruscan , Latin N, and Cyrillic Н.
Nun is believed to be derived from an Egyptian hieroglyph of a snake (the Hebrew word for snake, nachash begins with a Nun and snake in Aramaic is nun) or eel. Some have hypothesized a hieroglyph of fish in water as its origin (in Arabic, nūn means large fish or whale). The Phoenician letter was named nūn "fish", but the glyph has been suggested to descend from a hypothetical Proto-Canaanite naḥš "snake", based on the name in Ethiopic, ultimately from a hieroglyph representing a snake.