Really cool, as in A-1.

word used to explain something that is legendary or awesome

something that is top of the line, very hip
derived from a1 steak sauce
a is the best
1 is the best
steak sauce just sounds cooler

A nickname for a girl has a flat chest with a cup size of A1. The word comes from A1 steak sauce.

In other words: A1. First-class, excellent.

Something that is highly good. Reference of the Steak Sauce 'A1'

N. A stupid prostitute. Also known to hate pie and cake. Very annoying, you should approach with caution.