/ Dictionary / Index A A one: Meaning and Definition of Find definitions for: A one Pronunciation: (ā' wun'), [key] noting a vessel regarded by a shipping-classification society as being equipped to the highest standard and with equipment maintained in first-class condition. first-class; excellent; superior: The meals there are A one. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. Aomori AOR Related Content Daily Word Quiz: gregarious Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language