Alpha ALF-ə is the first letter of the Greek alphabet. In the system of Greek numerals, it has a value of one. Alpha is derived from the Phoenician letter aleph ⟨𐤀⟩, whose name comes from the West Semitic word for 'ox'. Letters that arose from alpha include the Latin letter ⟨A⟩ and the Cyrillic letter ⟨А⟩.