The Collaborative International Dictionary of English v.0.48:

Agglutinative \Ag*glu"ti*na*tive\, a. [Cf. F. agglutinatif.]
   1. Pertaining to agglutination; tending to unite, or having
      power to cause adhesion; adhesive.

   Syn: polysynthetic, holophrastic.
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   2. (Philol.) Formed or characterized by agglutination, as a
      language or a compound.
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            In agglutinative languages the union of words may be
            compared to mechanical compounds, in inflective
            languages to chemical compounds.      --R. Morris.
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            Cf. man-kind, heir-loom, war-like, which are
            agglutinative compounds. The Finnish, Hungarian,
            Turkish, the Tamul, etc., are agglutinative
            languages.                            --R. Morris.
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            Agglutinative languages preserve the consciousness
            of their roots.                       --Max
                                                  M["u]ller.
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WordNet (r) 3.0 (2006):

agglutinative
    adj 1: forming derivative or compound words by putting together
           constituents each of which expresses a single definite
           meaning [syn: agglutinative, polysynthetic]
    2: united as if by glue [syn: agglutinate, agglutinative]