Letters that make A-one
a, o, e, n are letters that make 'A-one'
1 possible definitions for 'A-one'
Under this definition, a-one is an adjective and has the following properties:
super, crack, ace, first-rate, tiptop, topnotch, top-notch, tops(p) have the same meaning as 'A-one'
'A-one' can be a useage of colloquialism.
superior is similar to A-one.