alpha

noun
al·​pha | \ˈal-fə \

Definition of alpha 

(Entry 1 of 2)

1 : the 1st letter of the Greek alphabet — see Alphabet Table

2 : something that is first : beginning

5 : the first version of a product (such as a computer program) that is being developed and tested usually used before another noun alpha versionsalpha testing also : a stage of product development in which alpha prototypes are released a product that is available in alpha — compare beta

alpha

adjective

Definition of alpha (Entry 2 of 2)

1 : closest in the structure of an organic molecule to a particular group or atom symbol α α-substitution

2 : socially dominant especially in a group of animals an alpha male

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Examples of alpha in a Sentence

Noun

money is not the alpha and omega—the beginning and end—of life's purpose

Recent Examples on the Web: Noun

The third type of omega-3, ALA, alpha-linolenic acid, comes from plant sources, like flaxseed and canola oil. Carolyn Todd, Allure, "Everything You Should Know Before Taking Fish Oil Supplements," 21 Aug. 2018 The Lone Star tick is thought to transmit a red-meat allergy through a Marvel heroine-sounding carbohydrate called alpha-gal, and can be diagnosed via blood test. Katie Heaney, The Cut, "Apparently Tick Bites Can Make You Allergic to Red Meat," 25 June 2018 In the wild, gorillas are part of large families with an alpha male at the top of the hierarchy. Hannah Rodriguez, The Seattle Times, "New ape in town: Kwame makes rare alpha-male debut at Woodland Park Zoo," 9 Nov. 2018 The premiere follows chimpanzees in the jungles of Senegal and Guinea, West Africa, and more specifically the challenges alpha male David faces after several years as the group's leader. Gabe Bergado, Teen Vogue, "BBC Earth's "Dynasties" Is a Captivating Look Into the Animal Kingdom," 9 Nov. 2018 If all thoroughbreds are alphas, Justify seems an extreme case, with a confidence bordering on arrogance, more pushy than regal. Liz Clarke, chicagotribune.com, "Justify's path to cusp of Triple Crown is unusual. But so is training a 1,380-pound athlete.," 7 June 2018 The book tells the story of the alpha female, O-Six, who became a favorite of wolf watchers and conservationists. The Editors, Outside Online, "Beyond Books Club: The 'American Wolf' Author Podcast," 9 July 2018 In the 1950s, an IBM engineer named Arthur Samuel created a checkers-playing program that learned in part by matching an alpha side against a beta side. Joshua Sokol, The Atlantic, "AI Keeps Mastering Games, But Can It Win in the Real World?," 27 Feb. 2018 Essentially the meat allergy is an allergy to the alpha-gal carbohydrate that's found in cows, pigs, sheep and other non-primates, but not humans. CBS News, "Red meat allergy transmitted by lone star ticks on the rise," 5 July 2018

Recent Examples on the Web: Adjective

More young talent is needed, but so is a nasty, alpha-type player who can set the tone up front and ease the burden on the secondary and linebackers. 2. Terez A. Paylor, kansascity, "Here are the Chiefs’ five biggest needs heading into next season | The Kansas City Star," 9 Mar. 2018 The enormous clouds emit large amounts of ultraviolet light with a spectral line produced by hydrogen ions, known as a Lyman-alpha line. Jay Bennett, Popular Mechanics, "Giant Glowing Space Blob's Power Source Discovered," 21 Sep. 2016 Actress Sydelle Noel embodies a similar ethos by taking on brawny, brassy, alpha woman roles. Abby Haglage, refinery29.com, "4 Black Girls With Big Dreams & The 4 Women Living Them," 13 July 2018 As the alpha brother, Romeo, wild, fun and charmingly manipulative, Pucci is transformed by a long, blond beard. Katie Walsh, latimes.com, "Review: Lou Taylor Pucci enlivens wild and wooly 'Poor Boy'," 12 July 2018 To combat those slips, the platform is adding visibility tools through a new feature, still in alpha testing, called Cloud Security Command Center. Lily Hay Newman, WIRED, "Google's Fix For the Gaffe Behind So Many Data Leaks," 21 Mar. 2018 He’s been surrounded all his life by alpha women — his late mother was a screaming, hard-drinking firecracker of a woman. New York Times, "Josh Brolin Fears the Summer of Josh Brolin," 20 June 2018 For state officials, a particular source of concern was alpha contamination, which was also found in some of the dust collected in previous years for Kaltofen’s study. Hal Bernton, The Seattle Times, "Study: Traces of radioactive contamination found in homes of six Hanford workers," 14 June 2018 At a summit where both men sought to play the alpha role, the optics were inherently in Trump’s favor. Laignee Barron, Time, "Body Language Experts Reveal What Trump and Kim's Behavior Says About the Singapore Summit," 12 June 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'alpha.' 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 alpha

Noun

13th century, in the meaning defined at sense 1

Adjective

1842, in the meaning defined at sense 1

History and Etymology for alpha

Noun

Middle English, from Latin, from Greek, of Semitic origin; akin to Hebrew āleph aleph

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Statistics for alpha

Last Updated

1 Dec 2018

Look-up Popularity

Time Traveler for alpha

The first known use of alpha was in the 13th century

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More Definitions for alpha

alpha

noun

Financial Definition of alpha

What It Is

The definition of alpha on InvestingAnswersAlpha, also known as "excess return" or "abnormal rate of return," is one of the most widely used measures of risk-adjusted performance. The number shows how much better or worse a fund performed relative to a benchmark. This difference is then attributed to the decisions made by the fund's management.

How It Works

Let's assume you are a portfolio manager who expects your client's portfolio to return 15% next year. The year goes by and the portfolio actually returns 16%. In its most basic sense, the alpha of the portfolio = 16% - 15% = 1%.

Mathematically speaking, alpha is the rate of return that exceeds what was expected or predicted by models like the capital asset pricing model (CAPM). To understand how it works, consider the CAPM formula:

r   =   Rf  + beta * (Rm - Rf )   +   alpha

where:
r = the security's or portfolio's return
Rf  = the risk-free rate of return
beta = the security's or portfolio's price volatility relative to the overall market
Rm  = the market return

The main part of the CAPM formula (except the excess-return factor) calculates what the rate of return on a certain security or portfolio ought to be under certain market conditions. Note that two similar portfolios might carry the same amount of risk (same beta) but because of different alphas, it's possible for one to generate higher returns than the other. This is a fundamental quandary for investors, who always want the highest return for the least amount of risk.

Why It Matters

The fundamental quandary for investors of how get the highest return possible for the least amount of risk can be measured by alpha. It is a measurable way to determine whether a manager's skill has added value to a fund on a risk-adjusted basis.

The very existence of alpha is controversial, however, because those who believe in the efficient market hypothesis (which says, among other things, that it is impossible to beat the market) attribute alpha to luck instead of skill, and base this belief on the fact that most managers fail to beat the market over the long-term.

Source: Investing Answers

alpha

noun

English Language Learners Definition of alpha

 (Entry 1 of 2)

: the first letter of the Greek alphabet

: the first version of a product (such as a computer program) that is being developed and tested

alpha

adjective

English Language Learners Definition of alpha (Entry 2 of 2)

: having the most power in a group of animals or people

alpha

noun
al·​pha | \ˈal-fə \

Medical Definition of alpha 

(Entry 1 of 2)

1 : the 1st letter of the Greek alphabet symbol Α or α

alpha

adjective
variants: or α-

Medical Definition of alpha (Entry 2 of 2)

1 : of or relating to one of two or more closely related chemical substances the alpha chain of hemoglobin α-yohimbine used somewhat arbitrarily to specify ordinal relationship or a particular physical form, especially one that is allotropic, isomeric, stereoisomeric, or sometimes polymeric (as in α-D-glucose)

2 : closest in position in the structure of an organic molecule to a particular group or atom also : occurring at or having a structure characterized by such a position α-substitution

More from Merriam-Webster on alpha

Thesaurus: All synonyms and antonyms for alpha

Britannica English: Translation of alpha for Arabic Speakers

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