from The American Heritage® Dictionary of the English Language, 5th Edition.

  • abbreviation accusative
  • abbreviation Games ace
  • abbreviation across
  • abbreviation adenine
  • abbreviation alto
  • abbreviation ampere
  • abbreviation angstrom
  • abbreviation answer
  • abbreviation area
  • abbreviation Sports assist

from Wiktionary, Creative Commons Attribution/Share-Alike License.

  • noun The first letter of the basic modern Latin alphabet.
  • noun Marks the first item in a list
  • noun A hypothetical item or person designated first when there are more than one.
  • noun computing The hexadecimal digit for 10
  • noun The first letter of the English alphabet, called a and written in the Latin script.
  • noun The ordinal number first, derived from this letter of the English alphabet, called a and written in the Latin script.
  • noun stock symbol Symbol for the company Agilent Technologies, Inc. on the NYSE.
  • noun chemistry, obsolete Symbol for the element Argon (Since 1956 has been changed to Ar).
  • noun geometry area
  • abbreviation physics ampere, a unit of electrical current.
  • abbreviation genetics IUPAC 1-letter abbreviation for adenine in genetic code.
  • abbreviation biochemistry IUPAC 1-letter abbreviation for alanine in proteins.
  • abbreviation vehicle-distinguishing signs Austria
  • noun The highest rank on any of various scales that assign letters.
  • noun education The highest letter grade assigned (disregarding plusses and minuses).
  • noun medicine A blood type that has a specific antigen that aggravates the immune response in people with type B antigen in their blood. They may receive blood from type A or type O, but cannot receive blood from AB or B.
  • noun chemistry Mass number.
  • noun acoustic source
  • noun actual weight of an aircraft
  • noun historical adulterer, adulteress
  • noun Alaska Steamship Company
  • noun Alcoa Steamship Company
  • noun allele dominant
  • noun alveolar gas
  • noun American Stock Exchange
  • noun ammunition examiner
  • noun Anchor Line
  • noun aspect ratio
  • noun Assembly Bill
  • noun Smallest of the brassiere cup sizes.
  • noun Chemical activity.
  • noun first van der Waals constant
  • noun Fraunhofer line for oxygen
  • noun aviation hail
  • noun includes extras
  • noun linear acceleration
  • noun mean sound absorption coefficient
  • noun Shoe size narrower than B
  • noun baseball Single A league, one of the lowest professional leagues.
  • noun Total acidity.


from Wiktionary, Creative Commons Attribution/Share-Alike License

From Ancient Greek letter Α (a, "alpha"), derived from the Phoenician letter 𐤀 (ʼ, "aleph").

from Wiktionary, Creative Commons Attribution/Share-Alike License

Abbreviation of various terms.


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  • The standard ratings are looking a little dated now, with just about everything on the market qualifying for an A, so at Marks & Spencer you'll find things rated AA and AAA; elsewhere it'll come up as A+ and A+++, but it all means the same thing, the plus or extra A means it goes 10% more efficiently than an A by itself.

    Lighten the load Guy Clapperton 2010

  • Promoted to Headline (H3) on 5/17/09: Bush-Obama: 'A rose by any other name 'yahooBuzzArticleHeadline =' Bush-Obama: \'A rose by any other name\ ''; yahooBuzzArticleSummary = 'Article: Who said, "A war criminal is a war ciminal is a war criminal?"'

    Bush-Obama: 'A rose by any other name' 2009

  • The four highest ratings at insurance specialist A.M. Best Co. are A++, A+, A and A -.

    How Well Do You Know... Annuities? 2008

  • A Quiet Excellence: an A+ yahooBuzzArticleHeadline = 'A Quiet Excellence: an A+ '; yahooBuzzArticleSummary =' Article: But there is an empty chair at the party.

    A Quiet Excellence: an A+ 2006

  • P lowered Portuguese long - and short-term ratings by two notches to 'A -/A-2' from 'A+/A - 1' - outlook is negative. Danske Bank A/S 2010

  • After initially rejecting a confusing appliance energy rating scheme that involved grades of A+++, A++, A+ and A, Europe's Trialogue parties of the European Council, European Commission and European Parliament accepted the scheme which would see consumers confused and A grades going to relatively energy inefficient products.

    WWF - Environmental News 2009

  • (IDR) to 'BBB+' from 'A -', senior debt rating to 'BBB' from 'BBB+', and Insurer Financial Strength (IFS) rating of its primary insurance subsidiaries to 'A' from 'A+'.

    unknown title 2009

  • (A-A″) 71B-Gal4/UAS-NkdGFP third-instar Drosophila salivary gland stained with α-Dsh and imaged for GFP (A) and Dsh (A′) distributions (merged image in A″).

    PLoS ONE Alerts: New Articles Jianhui Guo et al. 2009

  • The firm led the sale itself, and the bonds were rated A1 by Moody's Investors Service, A by Standard & Poor's and A+ by Fitch Ratings.

    Goldman Sachs Sells Katy Burne 2011

  • One achieved 10 A and A* grades at GCSE at a private school.

    Which school should I choose? Alice Douglas 2010


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