# Lambda

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Lambda (; [1] 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 (λάβδα) in Classical Greek times. [2] In Modern Greek the name of the letter, Λάμδα, is pronounced .

## Contents

In early Greek alphabets, the shape and orientation of lambda varied. [3] 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 &#923; and &#955; respectively. [4] The Unicode code points for lambda are U+039B and U+03BB.

## Symbol

### Upper-case letter Λ

Examples of the symbolic use of uppercase lambda include:

### Lower-case letter λ

Examples of the symbolic use of lowercase lambda include:

### Litra symbol

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 [15] 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). [16]

## Character encodings

Unicode uses the spelling "lamda" in character names, instead of "lambda", due to "preferences expressed by the Greek National Body". [17]

• Greek Lambda / Coptic Laula
Character information
PreviewΛλ
Unicode nameGREEK CAPITAL LETTER LAMDAGREEK SMALL LETTER LAMDAGREEK LETTER SMALL CAPITAL LAMDACOPTIC CAPITAL LETTER LAULACOPTIC SMALL LETTER LAULA
Encodingsdecimalhexdecimalhexdecimalhexdecimalhexdecimalhex
Unicode 923U+039B955U+03BB7463U+1D2711414U+2C9611415U+2C97
UTF-8 206 155CE 9B206 187CE BB225 180 167E1 B4 A7226 178 150E2 B2 96226 178 151E2 B2 97
Numeric character reference &#923;&#x39B;&#955;&#x3BB;&#7463;&#x1D27;&#11414;&#x2C96;&#11415;&#x2C97;
Named character reference &Lambda;&lambda;
DOS Greek 1388A162A2
DOS Greek-2 182B6229E5
Windows-1253 203CB235EB
TeX \Lambda\lambda
• Mathematical Lambda
Character information
Preview𝚲𝛌𝛬𝜆𝜦𝝀
Unicode nameMATHEMATICAL BOLD
CAPITAL LAMDA
MATHEMATICAL BOLD
SMALL LAMDA
MATHEMATICAL ITALIC
CAPITAL LAMDA
MATHEMATICAL ITALIC
SMALL LAMDA
MATHEMATICAL BOLD ITALIC
CAPITAL LAMDA
MATHEMATICAL BOLD ITALIC
SMALL LAMDA
Encodingsdecimalhexdecimalhexdecimalhexdecimalhexdecimalhexdecimalhex
Unicode 120498U+1D6B2120524U+1D6CC120556U+1D6EC120582U+1D706120614U+1D726120640U+1D740
UTF-8 240 157 154 178F0 9D 9A B2240 157 155 140F0 9D 9B 8C240 157 155 172F0 9D 9B AC240 157 156 134F0 9D 9C 86240 157 156 166F0 9D 9C A6240 157 157 128F0 9D 9D 80
UTF-16 55349 57010D835 DEB255349 57036D835 DECC55349 57068D835 DEEC55349 57094D835 DF0655349 57126D835 DF2655349 57152D835 DF40
Numeric character reference &#120498;&#x1D6B2;&#120524;&#x1D6CC;&#120556;&#x1D6EC;&#120582;&#x1D706;&#120614;&#x1D726;&#120640;&#x1D740;
Character information
Preview𝝠𝝺𝞚𝞴
Unicode nameMATHEMATICAL SANS-SERIF
BOLD CAPITAL LAMDA
MATHEMATICAL SANS-SERIF
BOLD SMALL LAMDA
MATHEMATICAL SANS-SERIF
BOLD ITALIC CAPITAL LAMDA
MATHEMATICAL SANS-SERIF
BOLD ITALIC SMALL LAMDA
Encodingsdecimalhexdecimalhexdecimalhexdecimalhex
Unicode 120672U+1D760120698U+1D77A120730U+1D79A120756U+1D7B4
UTF-8 240 157 157 160F0 9D 9D A0240 157 157 186F0 9D 9D BA240 157 158 154F0 9D 9E 9A240 157 158 180F0 9D 9E B4
UTF-16 55349 57184D835 DF6055349 57210D835 DF7A55349 57242D835 DF9A55349 57268D835 DFB4
Numeric character reference &#120672;&#x1D760;&#120698;&#x1D77A;&#120730;&#x1D79A;&#120756;&#x1D7B4;

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.

## Related Research Articles

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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.

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Lambda is the eleventh letter of the Greek alphabet that is λ, and capital form Λ.

## References

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2. Herbert Weir Smyth. A Greek Grammar for Colleges. I.1.c
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