The Collaborative International Dictionary of English v.0.48:

Pica \Pi"ca\, n. [L. pica a pie, magpie; in sense 3 prob. named
   from some resemblance to the colors of the magpie. Cf. Pie
   magpie.]
   1. (Zool.) The genus that includes the magpies.
      [1913 Webster]

   2. (Med.) A vitiated appetite that craves what is unfit for
      food, such as clay, chalk, ashes, coal, etc.;
      chthonophagia.

   Syn: allotriophagy.
        [1913 Webster]

   3. (R. C. Ch.) A service-book. See Pie. [Obs.]
      [1913 Webster]

   4. (Print.) A size of type next larger than small pica, and
      smaller than English.
      [1913 Webster]

   Note: Pica is twice the size of nonpareil, and is used as a
         standard of measurement in casting leads, cutting
         rules, etc., and also as a standard by which to
         designate several larger kinds of type, as double pica,
         two-line pica, four-line pica, and the like.
         [1913 Webster]

   Small pica (Print.), a size of type next larger than long
      primer, and smaller than pica.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

allotriophagy \al`lo*tri*oph"a*gy\
   ([a^]l`l[-o]*tr[i^]*[o^]f"[.a]*j[y^]), n. [Gr. 'allo`trios
   strange + fagei^n to eat: cf. F. allotriophagie.] (Med.)
   A depraved appetite; a desire for strange or nonnutritious
   food, such as clay or starch. Called also pica. --AS
   [1913 Webster]

WordNet (r) 3.0 (2006):

pica
    n 1: an eating disorder, frequent in children, in which non-
         nutritional objects are eaten persistently
    2: a linear unit (1/6 inch) used in printing [syn: em, pica
       em, pica]
    3: magpies [syn: Pica, genus Pica]