/ Dictionary / Index A aa: Meaning and Definition of Find definitions for: a•a Pronunciation: (ä'ä), [key] — n. basaltic lava having a rough surface. AA Pronunciation: [key] See See antiaircraft. See AA Pronunciation: [key] — Symbol. a proportional shoe width size, narrower than A and wider than AAA. the smallest proportional brassiere cup size. a quality rating for a corporate or municipal bond, lower than AAA and higher than A. a battery size for 1.5 volt dry cells: diameter, 0.6 in. (1.4 cm); length, 2 in. (5 cm). a designation for motion pictures certified as unsuitable for children under 14 unless accompanied by an adult. Cf. A (def. 11),(def. 5),(def. 9). aa Pronunciation: [key] — Symbol. (in prescriptions) ana. A.A. Pronunciation: [key] See antiaircraft. antiaircraft artillery. Associate in Accounting. See See a.a. Pronunciation: [key] See Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: aa (Thesaurus) A-1 AAA Related Content Daily Word Quiz: slough Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language