The Collaborative International Dictionary of English v.0.48:

ace \ace\ adj.
   1. of the highest quality an ace reporter

   Syn: A-one, first-class, first-rate, super, tip-top,
        topnotch(predicate)
        [WordNet 1.5]

The Collaborative International Dictionary of English v.0.48:

ace \ace\ v.
   to get a grade of "A"; as, to ace an exam. [Colloq.]
   [PJC]

The Collaborative International Dictionary of English v.0.48:

Ace \Ace\ ([=a]s), n.; pl. Aces ([=a]"s[e^]z). [OE. as, F. as,
   fr. L. as, assis, unity, copper coin, the unit of coinage.
   Cf. As.]
   [1913 Webster]
   1. A unit; a single point or spot on a card or die; the card
      or die so marked; as, the ace of diamonds.
      [1913 Webster]

   2. Hence: A very small quantity or degree; a particle; an
      atom; a jot.
      [1913 Webster]

            I 'll not wag an ace further.         --Dryden.
      [1913 Webster]

   3. (Sport) A single point won by a stroke, as in handball,
      rackets, etc.; in tennis, frequently, a point won by a
      service stroke.
      [Webster 1913 Suppl.]

   To bate an ace, to make the least abatement. [Obs.]

   Within an ace of, very near; on the point of. --W. Irving.
      [1913 Webster]

WordNet (r) 3.0 (2006):

ace
    adj 1: of the highest quality; "an ace reporter"; "a crack
           shot"; "a first-rate golfer"; "a super party"; "played
           top-notch tennis"; "an athlete in tiptop condition"; "she
           is absolutely tops" [syn: ace, A-one, crack,
           first-rate, super, tiptop, topnotch, top-notch,
           tops(p)]
    n 1: the smallest whole number or a numeral representing this
         number; "he has the one but will need a two and three to go
         with it"; "they had lunch at one" [syn: one, 1, I,
         ace, single, unity]
    2: one of four playing cards in a deck having a single pip on
       its face
    3: someone who is dazzlingly skilled in any field [syn: ace,
       adept, champion, sensation, maven, mavin,
       virtuoso, genius, hotshot, star, superstar, whiz,
       whizz, wizard, wiz]
    4: proteolytic enzyme that converts angiotensin I into
       angiotensin II [syn: angiotensin converting enzyme,
       angiotensin-converting enzyme, ACE]
    5: a major strategic headquarters of NATO; safeguards an area
       extending from Norway to Turkey [syn: Allied Command
       Europe, ACE]
    6: a serve that the receiver is unable to reach
    v 1: succeed at easily; "She sailed through her exams"; "You
         will pass with flying colors"; "She nailed her astrophysics
         course" [syn: breeze through, ace, pass with flying
         colors, sweep through, sail through, nail]
    2: score an ace against; "He aced his opponents"
    3: play (a hole) in one stroke
    4: serve an ace against (someone)

The Free On-line Dictionary of Computing (19 January 2023):

ACE

   1. Advanced Computing Environment.

   2. Adaptive Communication Environment.