An expert at something; a maverick, genius; a person owning a "first rank" talent.
A hole in one.
The ball marked with the number 1 in pool and related games.
A perfect score on a school exam.
A dollar bill.
A person who is asexual.
A military aircraft pilot who is credited with shooting down many enemy aircraft, typically five or more.
The best pitcher on the team.
Any of various hesperiid butterflies.
A card or die face so marked.
A single point or spot on a playing card or die normally indicating it as the prime, i.e. first and forefront. (in playing cards, of that series)
A point won by a single stroke, as in handball, rackets, etc.
A very small quantity or degree; a particle; an atom; a jot.
A serve won without the opponent hitting the ball.
To win a point by an ace.
To pass (a test, interviews etc.) perfectly.
To make an ace (hole in one).
Excellent.
Asexual, not experiencing sexual attraction.
The best of its kind
Describing a search algorithm that always returns the best result.
The best, most favourable or desirable, especially under some restriction.