The Collaborative International Dictionary of English v.0.48:

Apposition \Ap`po*si"tion\, n. [L. appositio, fr. apponere: cf.
   F. apposition. See Apposite.]
   1. The act of adding; application; accretion.
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            It grows . . . by the apposition of new matter.
                                                  --Arbuthnot.
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   2. The putting of things in juxtaposition, or side by side;
      also, the condition of being so placed.
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   3. (Gram.) The state of two nouns or pronouns, put in the
      same case, without a connecting word between them; as, I
      admire Cicero, the orator. Here, the second noun explains
      or characterizes the first.
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   Growth by apposition (Physiol.), a mode of growth
      characteristic of non vascular tissues, in which nutritive
      matter from the blood is transformed on the surface of an
      organ into solid unorganized substance.
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