Definition of beta in English:


Line breaks: beta
Pronunciation: /ˈbiːtə


  • 1The second letter of the Greek alphabet (Β, β), transliterated as ‘b’.
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    • But, just in right now, Tropical Storm Gamma, the third letter of the Greek alphabet, alpha, beta, gamma, delta, and so on and so on.
    • It probably had something to do with beta being the second letter in the Greek alphabet.
    • He named them using the first two letters of the Greek alphabet, alpha and beta.
  • 1.1 [as modifier] Denoting the second of a series of items, categories, forms of a chemical compound, etc.: beta carotene beta blocker
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    • For example, the babies are taught to be satisfied with their own caste of which there are five: alphas at the top, then betas, gammas, deltas, and epsilons at the bottom.
    • Does a fetus attain an alpha / beta / theta/delta brainwave state?
    • That smile. It shouts ‘hit me’ at every alpha male, and quite a few beta and zeta ones too.
  • 1.2British A second-class mark given for a piece of work or an examination paper.
  • 1.3 informal short for beta test.
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    • Like dtSearch, it offers a list of words as you type, although Google has offered a limited version of this feature in beta for its main search engine.
    • The online help files in our version were still in beta.
    • Firefox and Mac version in beta in a couple of months.
  • 1.4 (Beta) [followed by Latin genitive] Astronomy The second (typically second-brightest) star in a constellation: Beta Virginis
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    • These observation included that of the occultation of the star Beta Scorpii by the moon.
    • The orbiting pair in Beta Persei consists of a star that is a younger version of our sun, along with a hotter companion.
    • The vote was nearly unanimous, only Simon and a few officers who's planets had close ties to Beta Crucis.
  • 1.5 [as modifier] Relating to beta decay or beta particles: beta emitters
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    • By 1963, the year of my parent's marriage, the average release of beta emitters from reactor effluent was 14, 500 curies per day.
    • Titanium 45 has two forms, one a beta positive and gamma emitter with a half-life of 3.08 hours and a second form with a half-life of 21 days.
    • In addition, a number of radioisotopes, both natural and man-made, have been identified as beta emitters.
  • 1.6 (also beta coefficient) A measure of the movement in price of a security relative to the stock market as a whole, used to indicate possible risk: a fund with a beta of 0.58 is less volatile
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    • It we were to equate the rate of return on a bus firm's stock to the rate of return on the market portfolio (i.e. a beta coefficient of 1.0), then the risk-adjusted nominal cost of borrowing would be 25.03%.
    • At age 17 the beta coefficient for Personal Meaning was - 1.88, while that for the next strongest construct, Interpersonal Understanding, was -.77.
    • This point is illustrated by the reduction in the standardised beta coefficient of NA from .45.


via Latin from Greek.

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