lamb·​da | \ ˈlam-də How to pronounce lambda (audio) \

Definition of lambda

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

Examples of lambda in a Sentence

Recent Examples on the Web Like, what is the lambda in Lambda-CDM, and what is the CDM in Lambda-CDM, right? Rebecca Boyle, Quanta Magazine, "The Cosmologist Who Dreams in the Universe’s Dark Threads," 5 Nov. 2020 The bulk of the universe, 68 percent or so, is made of dark energy—represented by the Greek letter lambda (Λ)—an enigmatic repulsive force that drives the accelerating expansion of the universe. Michael Greshko, National Geographic, "Dark matter warps galaxy clusters more than expected, shaking up cosmic theory," 10 Sep. 2020 This is a predator named lambda, and its prey is an Escherichia coli bacterium. Rowan Jacobsen, Scientific American, "The World's First Virus-Proof Cell, with Redesigned DNA, Is About to Meet the Test of Its Life," 11 July 2019 It is divided by the upside-down V of the Greek lambda, the sigil falsely believed to have been painted on Spartan shields at Thermopylae. Myke Cole, The New Republic, "The Sparta Fetish Is a Cultural Cancer," 1 Aug. 2019 The Xi decays into a particle called the lambda baryon and three lighter particles, the K- (or kaon) and two pions. Fox News, "‘Charming’ heavy particle discovered at world’s largest atom smasher," 11 July 2017 However, the name is trademarked, and the project opted instead for lambda — the Greek letter used to symbolize wavelength. Wired Staff, WIRED, "Fast Track for Science Data," 17 Nov. 2003

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'lambda.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of lambda

15th century, in the meaning defined at sense 1

History and Etymology for lambda

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

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Time Traveler for lambda

Time Traveler

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

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Cite this Entry

“Lambda.” Dictionary, Merriam-Webster, Accessed 2 Mar. 2021.

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lamb·​da | \ ˈlam-də How to pronounce lambda (audio) \

Medical Definition of lambda

1 : the point of junction of the sagittal and lambdoid sutures of the skull

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