Word Study
a 1
CIDE DICTIONARY
a 1,
A registry mark given by underwriters (as at Lloyd's) to ships in first-class condition. Inferior grades are indicated by A 2 and A 3. [1913 Webster]
"A 1 is also applied colloquially to other things to imply superiority; prime; first-class; first-rate." [1913 Webster]
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