A1


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A1

Of the very highest caliber, standard, or quality. That was a positively A1 performance last night.
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.

A-one

Also, A-1; A-number-one. First-class, of the best quality, as in This is an A-one steak. The term comes from Lloyd's, the British insurance company, which in its 1775 shipping register designated the condition of a ship's hull by a letter grade (A, B, etc.) and of its cables, anchor, and other equipment by a number grade (1, 2, etc.). By the early 1800s A-1, the best possible grade, was being transferred to anything of superior quality.
The American Heritage® Dictionary of Idioms by Christine Ammer. Copyright © 2003, 1997 by The Christine Ammer 1992 Trust. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

A1

excellent; first-rate.
The full form of this expression is A1 at Lloyd's . In Lloyd's Register of Shipping, the phrase was used of ships in first-class condition as to the hull (A) and stores (1). The US equivalent is A No. 1 ; both have been in figurative use since the mid 19th century.
Farlex Partner Idioms Dictionary © Farlex 2017

A-1

and A number 1
mod. of the highest rating. This steak is really A-1!
McGraw-Hill's Dictionary of American Slang and Colloquial Expressions Copyright © 2006 by The McGraw-Hill Companies, Inc. All rights reserved.

A-1

The best quality. The term originated in the 1775 edition of Lloyd’s Register of British and Foreign Shipping, in which the state of a ship’s hull was designated by a letter grade and the condition of the anchor, cables, and so forth by a number grade. This insurance rating was soon transferred to numerous other areas and has been a cliché since the late nineteenth century.
The Dictionary of Clichés by Christine Ammer Copyright © 2013 by Christine Ammer