al·​pha | \ ˈal-fə How to pronounce alpha (audio) \

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 nounalpha versionsalpha testing also : a stage of product development in which alpha prototypes are released a product that is available in alpha — compare beta



Definition of alpha (Entry 2 of 2)

1 : closest in the structure of an organic molecule to a particular group or atom symbol αα-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 But Democrats are not very excited about alpha-dog businessmen and billionaires these days, especially media/tech billionaires who are also crotchety old skirt-chasing white guys. Kevin D. Williamson, National Review, "Mike Bloomberg Runs for President," 5 Dec. 2019 Trump, and his alpha-male projection of masculinity, also has appeal. Nicholas Riccardi, The Denver Post, "Gender gap widens among Hispanics who could be key in 2020," 23 Dec. 2019 The same survey found that the traits most valued among men were dependability, reliability, honesty, and loyalty, suggesting a cultural change from the alpha-male ideals of past generations. Brianna Holt, Quartz, "Film showed women that softboys are the emotionally intelligent men they wanted all along," 19 Dec. 2019 With an air of macho bluster, Trump seemed to be striving for a kind of alpha-male domination. Ben Zimmer, The Atlantic, "Why Trump Wouldn’t Say ‘Jockstrap’," 3 Oct. 2019 Its universe is one peopled almost entirely with white men looking to out-alpha male one another — a fantasy of the 1960s and not a reflection of the actual era. Barbara Vandenburgh, azcentral, "‘Ford v Ferrari’ is a well-oiled entertainment machine," 13 Nov. 2019 Almost all of them are in pre-alpha stage, not ready for consumer adoption. Steven Johnson, New York Times, "Beyond the Bitcoin Bubble," 16 Jan. 2018 First up are the Strawberry Rosé Complete Cleansing Towelettes, which deposit alpha lipoic acid (from the titular strawberries) and vitamin C onto skin while fully removing makeup — even the most stubborn waterproof varieties. Marci Robin, Allure, "A Hello Kitty Skin-Care Collection Is Coming to Ulta, and Everything Is Under $20," 24 Oct. 2019 Hey, this is guy talk, these are two alpha males talking to each other.’ Some bad (expletive) is said, absolutely. Matt Kawahara,, "Raiders’ Richie Incognito addresses past, denies bullying in HBO interview," 20 Sep. 2019 Recent Examples on the Web: Adjective Her most memorable creation, perhaps, is the enigmatic Lakey, the ur-alpha girl, who disappears for most of the novel but looms large in the imaginations of the other women. Megan Abbott, WSJ, "Five Best: Megan Abbott on Novels About Female Friendship," 9 Aug. 2018 The new game will likely arrive sometime next year, and is now in alpha testing. Eric Adams, Wired, "Bing Maps Make the Revived Flight Simulator Eerily Realistic," 15 Dec. 2019 So alpha Monocerotid takes its name from the alpha star and monoceros — or unicorn — constellation. Morgan Greene,, "Rare meteor outburst could light up the skies in the Chicago area on Thursday night: ‘Seeing that many is really special’," 20 Nov. 2019 With all due respect to both, each would appear to be more of a beta than alpha star. Ira Winderman,, "ASK IRA: Would D’Angelo Russell make sense for Heat?," 10 Nov. 2019 The first generation of these drugs were TNF-alpha agents that targeted the tumor necrosis factor to limit the immune response. Sun Pharmaceuticals, WIRED, "IL-23: The Master Regulator Behind Plaque Psoriasis," 30 Oct. 2019 Hey, this is guy talk, these are two alpha males talkin’ to each other.’ Was some bad s--- said? Scooby Axson,, "Incognito Denies Bullying Incident; Says Funeral Home Arrest Fueled By Drugs, Alcohol," 25 Sep. 2019 Hey, this is guy talk, these are two alpha males talkin’ to each other.’ Was some bad s— said? Cindy Boren, The Denver Post, "Richie Incognito admits to “a lot of crazy stuff in my past” but swears he’s “OK” now," 25 Sep. 2019 In rodents, defense against predators (interspecies) and alpha males (conspecifics) activates very similar brain structures and behaviors, suggesting that there was substantial convergent evolution of these defenses. Dean Mobbs, Scientific American, "On the Nature of Fear," 20 Sep. 2019

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


13th century, in the meaning defined at sense 1


1842, in the meaning defined at sense 1

History and Etymology for alpha


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

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Time Traveler for alpha

Time Traveler

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

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Statistics for alpha

Last Updated

13 Jan 2020

Cite this Entry

“Alpha.” The Dictionary, Merriam-Webster Inc., Accessed 26 January 2020.

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More Definitions for alpha



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

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


How to pronounce alpha (audio)

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



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

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


al·​pha | \ ˈal-fə How to pronounce alpha (audio) \

Medical Definition of alpha

 (Entry 1 of 2)

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


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

Comments on alpha

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to express in a more acceptable way

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