The Collaborative International Dictionary of English v.0.48:

Small \Small\ (sm[add]l), a. [Compar. Smaller
   (sm[add]l"[~e]r); superl. Smallest.] [OE. small, AS. smael;
   akin to D. smal narrow, OS. & OHG. smal small, G. schmal
   narrow, Dan. & Sw. smal, Goth. smals small, Icel. smali small
   cattle, sheep, or goats; cf. Gr. mh^lon a sheep or goat.]
   1. Having little size, compared with other things of the same
      kind; little in quantity or degree; diminutive; not large
      or extended in dimension; not great; not much;
      inconsiderable; as, a small man; a small river.
      [1913 Webster]

            To compare
            Great things with small.              --Milton.
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   2. Being of slight consequence; feeble in influence or
      importance; unimportant; trivial; insignificant; as, a
      small fault; a small business.
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   3. Envincing little worth or ability; not large-minded; --
      sometimes, in reproach, paltry; mean.
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            A true delineation of the smallest man is capable of
            interesting the greatest man.         --Carlyle.
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   4. Not prolonged in duration; not extended in time; short;
      as, after a small space. --Shak.
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   5. Weak; slender; fine; gentle; soft; not loud. "A still,
      small voice." --1 Kings xix. 12.
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   Great and small,of all ranks or degrees; -- used especially
      of persons. "His quests, great and small." --Chaucer.

   Small arms, muskets, rifles, pistols, etc., in distinction
      from cannon.

   Small beer. See under Beer.

   Small coal.
      (a) Little coals of wood formerly used to light fires.
          --Gay.
      (b) Coal about the size of a hazelnut, separated from the
          coarser parts by screening.

   Small craft (Naut.), a vessel, or vessels in general, of a
      small size.

   Small fruits. See under Fruit.

   Small hand, a certain size of paper. See under Paper.

   Small hours. See under Hour.

   Small letter. (Print.), a lower-case letter. See
      Lower-case, and Capital letter, under Capital, a.

   Small piece, a Scotch coin worth about 21/4d. sterling, or
      about 41/2cents.

   Small register. See the Note under 1st Register, 7.

   Small stuff (Naut.), spun yarn, marline, and the smallest
      kinds of rope. --R. H. Dana, Jr.

   Small talk, light or trifling conversation; chitchat.

   Small wares (Com.), various small textile articles, as
      tapes, braid, tringe, and the like. --M`Culloch.
      [1913 Webster]

WordNet (r) 3.0 (2006):

smaller
    adj 1: small or little relative to something else [syn:
           smaller, littler]

Moby Thesaurus II by Grady Ward, 1.0:

32 Moby Thesaurus words for "smaller":
   abated, ablated, attenuated, bated, belittled, consumed,
   contracted, curtailed, decreased, deflated, diminished, dissipated,
   dropped, eroded, fallen, fewer, less, lesser, lower, lowered,
   miniaturized, not so much, reduced, retrenched, scaled-down, shorn,
   shorter, shrunk, shrunken, watered-down, weakened, worn