ace

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. A single spot or pip on a playing card, die, or domino.
2. n. A playing card, die, or domino having one spot or pip.
3. n. In racket games:
4. n. A serve that one's opponent fails to hit.
5. n. A point scored by such a serve.
6. n. The act of hitting a golf ball in the hole with one's first shot.
7. n. A military aircraft pilot who has destroyed five or more enemy aircraft.
8. n. An expert in a given field.
9. adj. Top-notch; first-rate.
10. v. To serve an ace against in racket games.
11. v. To hit an ace on (a hole) in golf.
12. v. Slang To get the better of (someone): a candidate who aced his opponents in the primaries.
13. v. Slang To receive a grade of A on: She aced the exam.
14. v. Slang To perform with distinction on: aced the interview.
15. idiom. in the hole A hidden advantage or resource kept in reserve until needed.
16. idiom. within an ace of On the verge of; very near to: came within an ace of losing the election.

Century Dictionary and Cyclopedia

1. n. A unit; specifically, a single pip on a card or die, or a card or die marked with a single pip.
2. n. A very small quantity; a particle; an atom; a trifle: as, the creditor will not abate an ace of his demand.
3. n. A noun-suffix occurring in populace, pinnace, etc. (which see). It is not used as an English formative. In menace, grimace, and other words, the suffix is of different origin.

Wiktionary

1. n. A single point or spot on a playing card or die.
2. n. A card or die face so marked.
3. n. A very small quantity or degree; a particle; an atom; a jot.
4. n. tennis A serve won without the opponent hitting the ball.
5. n. baseball The best pitcher on the team.
6. n. baseball, dated, 19th century A run.
7. n. golf A hole in one.
8. n. An expert at something.
9. n. A military aircraft pilot who is credited with shooting down five or more enemy aircraft.
10. n. A perfect score on a school exam.
11. v. To pass (a test, interviews etc.) perfectly.
12. v. tennis To win a point by an ace.
13. v. golf To make an ace (hole in one).
14. adj. UK, slang Excellent.

GNU Webster's 1913

1. n. A unit; a single point or spot on a card or die; the card or die so marked.
2. n. Hence: A very small quantity or degree; a particle; an atom; a jot.
3. n. (Sport) A single point won by a stroke, as in handball, rackets, etc.; in tennis, frequently, a point won by a service stroke.
4. adj. of the highest quality.
5. v. colloq. to get a grade of "A".

WordNet 3.0

1. adj. of the highest quality
2. v. succeed at easily
3. v. score an ace against
4. v. play (a hole) in one stroke
5. v. serve an ace against (someone)
6. n. the smallest whole number or a numeral representing this number
7. n. one of four playing cards in a deck having a single pip on its face
8. n. a major strategic headquarters of NATO; safeguards an area extending from Norway to Turkey
9. n. a serve that the receiver is unable to reach
10. n. proteolytic enzyme that converts angiotensin I into angiotensin II
11. n. someone who is dazzlingly skilled in any field