The Collaborative International Dictionary of English v.0.48:

Top \Top\, n. [AS. top; akin to OFries. top a tuft, D. top top,
   OHG. zopf end, tip, tuft of hair, G. zopf tuft of hair,
   pigtail, top of a tree, Icel. toppr a tuft of hair, crest,
   top, Dan. top, Sw. topp pinnacle, top; of uncertain origin.
   Cf. Tuft.]
   1. The highest part of anything; the upper end, edge, or
      extremity; the upper side or surface; summit; apex;
      vertex; cover; lid; as, the top of a spire; the top of a
      house; the top of a mountain; the top of the ground.
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            The star that bids the shepherd fold,
            Now the top of heaven doth hold.      --Milton.
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   2. The utmost degree; the acme; the summit.
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            The top of my ambition is to contribute to that
            work.                                 --Pope.
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   3. The highest rank; the most honorable position; the utmost
      attainable place; as, to be at the top of one's class, or
      at the top of the school.
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            And wears upon his baby brow the round
            And top of sovereignty.               --Shak.
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   4. The chief person; the most prominent one.
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            Other . . . aspired to be the top of zealots.
                                                  --Milton.
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   5. The crown of the head, or the hair upon it; the head.
      "From top to toe" --Spenser.
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            All the stored vengeance of Heaven fall
            On her ungrateful top !               --Shak.
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   6. The head, or upper part, of a plant.
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            The buds . . . are called heads, or tops, as
            cabbageheads.                         --I. Watts.
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   7. (Naut.) A platform surrounding the head of the lower mast
      and projecting on all sudes. It serves to spead the
      topmast rigging, thus strengheningthe mast, and also
      furnishes a convenient standing place for the men aloft.
      --Totten.
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   8. (Wool Manuf.) A bundle or ball of slivers of comkbed wool,
      from which the noils, or dust, have been taken out.
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   9. Eve; verge; point. [R.] "He was upon the top of his
      marriage with Magdaleine." --Knolles.
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   10. The part of a cut gem between the girdle, or
       circumference, and the table, or flat upper surface.
       --Knight.
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   11. pl. Top-boots. [Slang] --Dickens.
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   12. (Golf)
       (a) A stroke on the top of the ball.
       (b) A forward spin given to the ball by hitting it on or
           near the top.
           [Webster 1913 Suppl.]

   Note: Top is often used adjectively or as the first part of
         compound words, usually self-explaining; as, top stone,
         or topstone; top-boots, or top boots; top soil, or
         top-soil.
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   Top and but (Shipbuilding), a phrase used to denote a
      method of working long tapering planks by bringing the but
      of one plank to the top of the other to make up a constant
      breadth in two layers.

   Top minnow (Zool.), a small viviparous fresh-water fish
      (Gambusia patruelis) abundant in the Southern United
      States. Also applied to other similar species.

   From top to toe, from head to foot; altogether.
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