|Use in other languages|
Lambda ( // ; 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 . 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] .
In early Greek alphabets, the shape and orientation of lambda varied.Most variants consisted of two straight strokes, one longer than the other, connected at their ends. The angle might be in the upper-left, lower-left ("Western" alphabets) or top ("Eastern" alphabets). Other variants had a vertical line with a horizontal or sloped stroke running to the right. With the general adoption of the Ionic alphabet, Greek settled on an angle at the top; the Romans put the angle at the lower-left.
The HTML 4 character entity references for the Greek capital and small letter lambda are
λ respectively. The Unicode code points for lambda are U+039B and U+03BB.
Examples of the symbolic use of uppercase lambda include:
This section has multiple issues. Please help improve it or discuss these issues on the talk page . (Learn how and when to remove these template messages)
Examples of the symbolic use of lowercase lambda include:
The Roman libra and Byzantine lítra (λίτρα), which served as both the pound mass unit and liter volume unit, were abbreviated in Greek using lambda with modified forms of the iota subscript (as λͅ). These are variously encoded in Unicode. The Ancient Greek Numbers Unicode block includes 10183 GREEK LITRA SIGN (𐆃) as well as 𐅢, which is described as 10162 GREEK ACROPHONIC HERMIONIAN TEN but was much more common as a form of the litra sign. A variant of the sign can be formed from 0338 COMBINING LONG SOLIDUS OVERLAY and either 039B GREEK CAPITAL LETTER LAMDA (Λ̸) or 03BB GREEK SMALL LETTER LAMDA (λ̸).
Unicode uses the spelling "lamda" in character names, instead of "lambda", due to "preferences expressed by the Greek National Body".
|Unicode name||GREEK CAPITAL LETTER LAMDA||GREEK SMALL LETTER LAMDA||GREEK LETTER SMALL CAPITAL LAMDA||COPTIC CAPITAL LETTER LAULA||COPTIC SMALL LETTER LAULA|
|UTF-8||206 155||CE 9B||206 187||CE BB||225 180 167||E1 B4 A7||226 178 150||E2 B2 96||226 178 151||E2 B2 97|
|Numeric character reference||Λ||Λ||λ||λ||ᴧ||ᴧ||Ⲗ||Ⲗ||ⲗ||ⲗ|
|Named character reference||Λ||λ|
|Unicode name||MATHEMATICAL BOLD|
|MATHEMATICAL BOLD ITALIC|
|MATHEMATICAL BOLD ITALIC|
|UTF-8||240 157 154 178||F0 9D 9A B2||240 157 155 140||F0 9D 9B 8C||240 157 155 172||F0 9D 9B AC||240 157 156 134||F0 9D 9C 86||240 157 156 166||F0 9D 9C A6||240 157 157 128||F0 9D 9D 80|
|UTF-16||55349 57010||D835 DEB2||55349 57036||D835 DECC||55349 57068||D835 DEEC||55349 57094||D835 DF06||55349 57126||D835 DF26||55349 57152||D835 DF40|
|Numeric character reference||𝚲||𝚲||𝛌||𝛌||𝛬||𝛬||𝜆||𝜆||𝜦||𝜦||𝝀||𝝀|
|Unicode name||MATHEMATICAL SANS-SERIF|
BOLD CAPITAL LAMDA
BOLD SMALL LAMDA
BOLD ITALIC CAPITAL LAMDA
BOLD ITALIC SMALL LAMDA
|UTF-8||240 157 157 160||F0 9D 9D A0||240 157 157 186||F0 9D 9D BA||240 157 158 154||F0 9D 9E 9A||240 157 158 180||F0 9D 9E B4|
|UTF-16||55349 57184||D835 DF60||55349 57210||D835 DF7A||55349 57242||D835 DF9A||55349 57268||D835 DFB4|
|Numeric character reference||𝝠||𝝠||𝝺||𝝺||𝞚||𝞚||𝞴||𝞴|
These characters are used only as mathematical symbols. Stylized Greek text should be encoded using the normal Greek letters, with markup and formatting to indicate text style.
|Look up Λ or λ in Wiktionary, the free dictionary.|
Epsilon is the fifth letter of the Greek alphabet, corresponding phonetically to a mid front unrounded vowel. In the system of Greek numerals it also has the value five. It was derived from the Phoenician letter He . Letters that arose from epsilon include the Roman E, Ë and Ɛ, and Cyrillic Е, È, Ё, Є and Э.
Eta is the seventh letter of the Greek alphabet. Originally denoting the consonant /h/, its sound value in the classical Attic dialect of Ancient Greek was a long vowel, raised to [i] in hellenistic Greek, a process known as iotacism.
Gamma is the third letter of the Greek alphabet. In the system of Greek numerals it has a value of 3. In Ancient Greek, the letter gamma represented a voiced velar stop. In Modern Greek, this letter represents either a voiced velar fricative or a voiced palatal fricative.
Omega is the 24th and final letter in the Greek alphabet. In the Greek numeric system/Isopsephy (Gematria), it has a value of 800. The word literally means "great O", as opposed to Ο ο omicron, which means "little O".
Chi is the 22nd letter of the Greek alphabet.
Phi is the 21st letter of the Greek alphabet.
Tau is the 19th letter of the Greek alphabet. In the system of Greek numerals it has a value of 300.
Xi is the 14th letter of the Greek alphabet. It is pronounced [ksi] in Modern Greek, and generally or in English. In the system of Greek numerals, it has a value of 60. Xi was derived from the Phoenician letter samekh .
Nu is the 13th letter of the Greek alphabet. In the system of Greek numerals it has a value of 50. It is derived from the ancient Phoenician language nun . Its Latin equivalent is N, though the lowercase resembles the Roman lowercase v.
Mu or my is the 12th letter of the Greek alphabet. In the system of Greek numerals it has a value of 40. Mu was derived from the Egyptian hieroglyphic symbol for water, which had been simplified by the Phoenicians and named after their word for water, to become 𐤌 (mem). Letters that derive from mu include the Roman M and the Cyrillic М.
Sigma is the eighteenth letter of the Greek alphabet. In the system of Greek numerals, it has a value of 200. In general mathematics, uppercase ∑ is used as an operator for summation. When used at the end of a letter-case word, the final form (ς) is used. In Ὀδυσσεύς (Odysseus), for example, the two lowercase sigmas (σ) in the center of the name are distinct from the word-final sigma (ς) at the end.
Kappa is the 10th letter of the Greek alphabet, used to represent the  sound in Ancient and Modern Greek. In the system of Greek numerals, Kʹ has a value of 20. It was derived from the Phoenician letter kaph . Letters that arose from kappa include the Roman K and Cyrillic К.
Rho is the 17th letter of the Greek alphabet. In the system of Greek numerals it has a value of 100. It is derived from Phoenician letter res . Its uppercase form uses the same glyph, Ρ, as the distinct Latin letter P; the two letters have different Unicode encodings.
Psi is the 23rd letter of the Greek alphabet and has a numeric value of 700. In both Classical and Modern Greek, the letter indicates the combination /ps/.
The Greek alphabet has been used to write the Greek language since the late ninth or early eighth century BC. It is derived from the earlier Phoenician alphabet, and was the first alphabetic script in history to have distinct letters for vowels as well as consonants. In Archaic and early Classical times, the Greek alphabet existed in many local variants, but, by the end of the fourth century BC, the Euclidean alphabet, with twenty-four letters, ordered from alpha to omega, had become standard and it is this version that is still used to write Greek today.
Greek letters are used in mathematics, science, engineering, and other areas where mathematical notation is used as symbols for constants, special functions, and also conventionally for variables representing certain quantities. In these contexts, the capital letters and the small letters represent distinct and unrelated entities. Those Greek letters which have the same form as Latin letters are rarely used: capital A, B, E, Z, H, I, K, M, N, O, P, T, Y, X. Small ι, ο and υ are also rarely used, since they closely resemble the Latin letters i, o and u. Sometimes font variants of Greek letters are used as distinct symbols in mathematics, in particular for ε/ϵ and π/ϖ. The archaic letter digamma (Ϝ/ϝ/ϛ) is sometimes used.
Unicode has a certain amount of duplication of characters. These are pairs of single Unicode code points that are canonically equivalent. The reason for this are compatibility issues with legacy systems.
L, or l, is the twelfth letter of the modern English alphabet and the ISO basic Latin alphabet. Its name in English is el, plural els.
In mathematical logic and computer science the symbol has taken the name turnstile because of its resemblance to a typical turnstile if viewed from above. It is also referred to as tee and is often read as "yields", "proves", "satisfies" or "entails".
Lambda is the eleventh letter of the Greek alphabet that is λ, and capital form Λ.