lambda

noun

lamb·​da ˈlam-də How to pronounce lambda (audio)
1
: the 11th letter of the Greek alphabet see Alphabet Table
2
: an uncharged unstable elementary particle that has a mass 2183 times that of an electron and that decays typically into a nucleon and a pion

Word History

Etymology

Middle English, from Greek, of Semitic origin; akin to Hebrew lāmedh lamed

First Known Use

15th century, in the meaning defined at sense 1

Time Traveler
The first known use of lambda was in the 15th century

Dictionary Entries Near lambda

lambaste

lambda

lambda point

See More Nearby Entries 

Cite this Entry

“Lambda.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/lambda. Accessed 29 Nov. 2024.

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Kids Definition

lambda

noun
lamb·​da ˈlam-də How to pronounce lambda (audio)
: the eleventh letter of the Greek alphabet
—Λ or λ

Medical Definition

lambda

noun
lamb·​da ˈlam-də How to pronounce lambda (audio)
1
: the point of junction of the sagittal and lambdoid sutures of the skull
2
: bacteriophage lambda

More from Merriam-Webster on lambda

Britannica.com: Encyclopedia article about lambda

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