triple A(redirected from Achalasia-Addisonian Syndrome)
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The highest bond rating by S&P and Fitch. A rating of AAA is considered to carry virtually no risk; U.S. Treasury securities, for example, always receive the AAA rating. A bond with an AA is investment-grade, meaning that banks are allowed to hold them. AA bonds are low risk and low return. The rating is equivalent of an Aaa rating by Moody's.