be·​ta | \ ˈbā-tə How to pronounce beta (audio) , chiefly British ˈbē- \

Definition of beta

 (Entry 1 of 2)

1 : the 2nd letter of the Greek alphabet — see Alphabet Table
3 : a measure of the risk potential of a stock or an investment portfolio expressed as a ratio of the stock's or portfolio's volatility to the volatility of the market as a whole
4 : a nearly complete prototype of a product (such as software) the beta version also : a stage of development in which a product is nearly complete but not yet ready for release released in beta



Definition of beta (Entry 2 of 2)

: second in position in the structure of an organic molecule from a particular group or atom beta substitution often used in combination symbol β

Examples of beta in a Sentence

Noun a program that is currently in beta
Recent Examples on the Web: Noun Blizzard has temporarily disabled Wrecking Ball in the beta. Kris Holt, Forbes, 3 May 2022 Also included in recent updates is a new Android app that is currently in beta. Zach Epstein, BGR, 30 Apr. 2022 The service is launching in beta in the coming weeks, and the companieswill be delivering their inaugural presentation at Music Biz 2022 in Nashville on May 11th at 12:30 PM. Jem Aswad, Variety, 29 Apr. 2022 GeForce Now boasts more than 1,000 games that can be streamed to a Windows PCs, Macs, Android (including Android TV), Chrome, Safari, select LG TVs, and is currently in beta for the Edge browser. Matthew Humphries, PCMAG, 29 Apr. 2022 The software is still in beta, and is far from fully autonomous in spite of its name. Allison Morrow, CNN, 26 Apr. 2022 Billing itself as inexpensive and speedy to use, the network, still in beta, has enticed developers big and small to build a variety of apps and projects on Solana. Declan Harty, Fortune, 12 Apr. 2022 Since launching in beta mode less than three months ago, Flowty has processed over 150 loans with an average size of $4,000-5,000. Nina Bambysheva, Forbes, 22 Apr. 2022 Khloé is in the dressing room pre-gaming with some champagne and mom's beta blockers when WW spokesman James Corden arrives to give her a pep talk about dealing with the haters. Kristen Baldwin,, 21 Apr. 2022 Recent Examples on the Web: Adjective The new single shot is designed to target two strains of the coronavirus using a combination of a beta variant-specific vaccine and the company's original formula, NBC News reported. Alexandra Schonfeld,, 20 Apr. 2022 Houston Outlaws will give beta keys to 50 lucky fans. Kris Holt, Forbes, 14 Apr. 2022 Buyers and sellers already on the Whip Media Exchange, which had a beta launch in 2021, include Lionsgate, Pluto TV, Globo, TelevisaUnivision’s ViX, AMC Networks International Latin America, Vodafone Hungary, Tastemade and Keshet International. J. Clara Chan, The Hollywood Reporter, 29 Mar. 2022 White House press secretary Jen Psaki said Tuesday the site is in its beta phase to allow troubleshooting. Amy Nakamura, USA TODAY, 19 Jan. 2022 Google says that the multisearch feature is now available as a beta feature in English in the US. Jacob Siegal, BGR, 7 Apr. 2022 Many beta defensin genes have also been discovered in the human genome, however only three have been classified at the functional level. William A. Haseltine, Forbes, 26 Mar. 2022 But a single mutation on chromosome 11 modifies the beta unit. Dhruv Khullar, The New Yorker, 22 Mar. 2022 The major difference, though, is that Decentraland is up and running, whereas The Sandbox is still beta testing, and rolling out updates and developments but is currently open to all. Fortune, 16 Mar. 2022 See More

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

First Known Use of beta


14th century, in the meaning defined at sense 1


1862, in the meaning defined above

History and Etymology for beta


Middle English betha, from Latin beta, from Greek bēta, of Semitic origin; akin to Hebrew bēth beth

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The first known use of beta was in the 14th century

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Last Updated

8 May 2022

Cite this Entry

“Beta.” Dictionary, Merriam-Webster, Accessed 18 May. 2022.

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More Definitions for beta


be·​ta | \ ˈbāt-ə, chiefly British ˈbē-tə \

Medical Definition of beta

 (Entry 1 of 2)

1 : the second letter of the Greek alphabet symbol Β or β
3 : beta wave


variants: or β-

Medical Definition of beta (Entry 2 of 2)

1 : of or relating to one of two or more closely related chemical substances the beta chain of hemoglobin β-yohimbine used somewhat arbitrarily to specify ordinal relationship or a particular physical form and especially one that is allotropic, isomeric, stereoisomeric, or sometimes polymeric (as in β-D-glucose)
2 : second in position in the structure of an organic molecule from a particular group or atom also : occurring at or having a structure characterized by such a position beta substitution
3 : producing a zone of decolorization when grown on blood media used of some hemolytic streptococci or of the hemolysis they cause

More from Merriam-Webster on beta

Nglish: Translation of beta for Spanish Speakers

Britannica English: Translation of beta for Arabic Speakers Encyclopedia article about beta


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