- noting a vessel regarded by a shipping-classification society as being equipped to the highest standard and with equipment maintained in first-class condition.
- Also A number one. Informal. first-class; excellent; superior: The meals there are A one.
Also A-one, A 1, A-1.
Origin of A one
First recorded in 1830–40
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Examples from the Web for a1
A1: Joshua, I think the most honest answer I can give to this two-part question is: Yes.Justin Bieber's Spiritual Crisis
January 26, 2014
A1 was too sci-fi, A4 not dramatic enough, so I could simply terminate these threads.A Mathematically Impossible Novel: Manil Suri Explains “The City of Devi”
March 15, 2013
An A1 piece of villainy was on, and they were conversing in low tones.Thoroughbreds
W. A. Fraser
One instance each of A-1 and A1, and cooee and coo-e-e were retained.The Jolliest School of All
I've got some A1 inventions here, an' I want to get 'em patented.The Panchronicon
Harold Steele Mackaye
When at rest they all press upwards against the plates A and A1 respectively.How it Works
Mrs. Bax, now that her true nature was revealed, proved to be A1.New Treasure Seekers
E. (Edith) Nesbit
A-1 or A-one
- in good health; physically fit
- informal first class; excellent
- (of a vessel) with hull and equipment in first-class condition
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012