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.
Someone who is an expert in, or devoted to, some specific branch of study or research.
A stenotopic species.
A physician whose practice is limited to a particular branch of medicine or surgery.
Any of several non-commissioned ranks corresponding to that of corporal.
An organism that is specialized for a particular environment.
Specialised, involving detailed knowledge of a restricted topic.