[1] : The Collaborative International Dictionary of English v.0.48

contribute \contrib"ute\, v. t. imp.  p. p. contributed; p.
   pr.  vb. n. contributing. l. contributus, p. p. of
   contribuere to bring together, to add; con- + tribuere to
   grant, impart. see tribute.
   to give or grant i common with others; to give to a common
   stock or for a common purpose; to furnish or suply in part;
   to give money or other aid for a specified object; as, to
   contribute food or fuel for the poor.
   1913 webster

         england contributes much more than any other of the
         allies.                                  --addison.
   1913 webster
see also:
contributed contributing tribute 

[2] : WordNet (r) 2.0

contributing
     adj : tending to bring about; being partly responsible for;
           "working conditions are not conducive to productivity";
           "the seaport was a contributing factor in the growth of
           the city"; "a contributory factor" syn: conducive, contributinga,
            contributive, contributory, tributary
see also:
conducive contributinga contributive contributory tributary 

Contributing >> C Words
Contributing, definition of term: Contributing
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