[1] : The Collaborative International Dictionary of English v.0.48

ace \ace\ =as, n.; pl. aces =a"se^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
see also:
aces as to bate an ace within an ace of 

Ace >> A Words
Ace, definition of term: Ace
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