lambda
Lambda (/ˈlæmdə/) uppercase Λ, lowercase λ; Greek: λάμ(β)δα, lám(b)da) is the 11th letter of the Greek alphabet, representing the sound /l/. In the system of Greek numerals, lambda has a value of 30. Lambda is derived from the Phoenician Lamed Lamedh. Lambda gave rise to the Latin L and the Cyrillic El (Л). The ancient grammarians and dramatists give evidence to the pronunciation as [laːbdaː] (λάβδα) in Classical Greek times. In Modern Greek, the name of the letter, Λάμδα, is pronounced [ˈlam.ða].