alpha

American  

[al-fuh] / ˈæl fə /

noun

1. the first letter of the Greek alphabet (A, α).

2. the vowel sound represented by the first letter of the Greek alphabet.

3. the first; the beginning.

4. Astronomy. Alpha, used to designate the brightest star in a constellation.

   Alpha Arietis is the brightest star in Aries.

5. Chemistry. one of two or more isomeric compounds.

6. the first in a series of related items: frequently used in chemistry and physics.

7. Computers. an early phase of hardware or software development, in which the product is tested by its developers or manufacturers.

   Some modules are complete and ready for consumers while others are still in alpha.

8. Chiefly British. a mark or grade corresponding to an A.

9. alpha male.

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adjective

1. 1. (of an animal) having the highest rank in a dominance hierarchy.

      the alpha female of an elephant pack.

   2. being the most dominant, powerful, or assertive person in a particular group.

   3. Slang: Sometimes Disparaging. being or relating to a man who is perceived to be assertive, successful, and sexually dominant.

2. alphabetical.

   Put the files in alpha order.

3. Computers. being, relating to, or undergoing the early phase of product development in which a product is tested by its developers or manufacturers.

   The initial release is really an alpha version only available to developers.

4. Chemistry. relating to or linked to the carbon atom closest to a particular group in an organic molecule.

alpha ¹ British  

/ ˈælfə /

noun

1. the first letter in the Greek alphabet (Α, α), a vowel transliterated as a

2. the highest grade or mark, as in an examination

3. (modifier)

   1. involving or relating to helium-4 nuclei

      an alpha particle

   2. relating to one of two or more allotropes or crystal structures of a solid

      alpha iron

   3. relating to one of two or more isomeric forms of a chemical compound, esp one in which a group is attached to the carbon atom to which the principal group is attached

4. (modifier) denoting the dominant person or animal in a group

   the alpha male

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Alpha ² British  

/ ˈælfə /

noun

1. (foll by the genitive case of a specified constellation) usually the brightest star in a constellation

   Alpha Centauri

2. communications a code word for the letter a

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Etymology

Origin of alpha

First recorded in 1150–1200; from Latin, from Greek álpha, from Phoenician 'lp “ox,” also the name of the first letter of the Phoenician alphabet; aleph

Example Sentences

Nivola, in a particularly tough role, displays a heady mix of alpha machismo, tenderness and contempt that is just as funny as it needs to be without losing a crucial dimensionality.

From Los Angeles Times • Apr. 3, 2026

Unfortunately, a short seller couldn’t have turned a profit with these stocks, because the 81.4% negative alpha didn’t reflect borrowing costs.

From MarketWatch • Mar. 27, 2026

Although Line Intensity Mapping has been used before, this is the first time it has mapped Lyman alpha emission with such a large dataset and such high accuracy.

From Science Daily • Mar. 8, 2026

Mr. James’s tone—that of a reformed alpha male, an ex-con and traveler of a gritty road—lends his tale authenticity.

From The Wall Street Journal • Mar. 1, 2026

One day he told Seaborg triumphantly that he had found an alpha emitter and had already ruled out that it could be an isotope of element 91, 92, or 93.

From "Big Science" by Michael Hiltzik