Lambda

Lambda, sometimes rendered lamda, labda or lamma, is the eleventh letter of the Greek alphabet, representing the voiced alveolar lateral approximant IPA: [l]; it derives from the Phoenician letter Lamed, and gave rise to Latin L and Cyrillic El (Л). In the system of Greek numerals, lambda has a value of 30. The ancient grammarians typically called it λάβδα in Classical Greek times, whereas in Modern Greek it is λάμδα, while the spelling λάμβδα was used throughout the lengthy transition between the two. Read more on Wikipedia