Source : Webster's Revised Unabridged Dictionary (1913)

Runt \Runt\, n. [Written also {rant}.] [Scot. runt an old cow,
   an old, withered woman, a hardened stem or stalk, the trunk
   of a tree; cf. D. rund a bullock, an ox or cow, G. rind. Cf.
   {Rother}, a.]
   1. (Zo["o]l.) Any animal which is unusually small, as
      compared with others of its kind; -- applied particularly
      to domestic animals.

   2. (Zo["o]l.) A variety of domestic pigeon, related to the
      barb and carrier.

   3. A dwarf; also, a mean, despicable, boorish person; -- used
      opprobriously.

            Before I buy a bargain of such runts, I'll buy a
            college for bears, and live among 'em. --Beau. & Fl.

   4. The dead stump of a tree; also, the stem of a plant. [Obs.
      or Prov. Eng.] --Halliwell.

            Neither young poles nor old runts are durable.
                                                  --Holland.

Source : WordNet®

runt
     n : disparaging terms for small people [syn: {shrimp}, {peewee},
          {half-pint}]