The Collaborative International Dictionary of English v.0.48:

Contribute \Con*trib"ute\, v. i.
   1. To give a part to a common stock; to lend assistance or
      aid, or give something, to a common purpose; to have a
      share in any act or effect.
      [1913 Webster]

            We are engaged in war; the secretary of state calls
            upon the colonies to contribute.      --Burke.
      [1913 Webster]

   2. To give or use one's power or influence for any object; to
      assist.
      [1913 Webster]

            These men also contributed to obstruct the progress
            of wisdom.                            --Goldsmith.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Contribute \Con*trib"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]

WordNet (r) 3.0 (2006):

contribute
    v 1: bestow a quality on; "Her presence lends a certain cachet
         to the company"; "The music added a lot to the play"; "She
         brings a special atmosphere to our meetings"; "This adds a
         light note to the program" [syn: lend, impart,
         bestow, contribute, add, bring]
    2: contribute to some cause; "I gave at the office" [syn:
       contribute, give, chip in, kick in]
    3: be conducive to; "The use of computers in the classroom lead
       to better writing" [syn: contribute, lead, conduce]
    4: provide; "The city has to put up half the required amount"
       [syn: put up, contribute]

Moby Thesaurus II by Grady Ward, 1.0:

98 Moby Thesaurus words for "contribute":
   accommodate, add to, advance, afford, aid, assist, augment,
   be enfranchised, be implicated in, bear a hand, bend to, bestow,
   bias, chip in, clothe, come through, compare, conduce,
   contribute to, dispose, donate, donate to, endow, enter into, fill,
   fill up, find, fortify, forward, fund, furnish, gift, gift with,
   give, give to, go, go into, grant, have a tendency, have suffrage,
   head, help, help decide, incline, invest, join, join in, keep,
   kick in, lead, lean, look to, maintain, make available,
   make provision for, make the scene, partake, partake of,
   participate, participate in, pitch in, pledge, point, point to,
   prepare, present, promote, provide, provide for, pull an oar,
   recruit, redound to, reinforce, replenish, serve, set, set toward,
   show a tendency, sit in, sit in on, stock, store, strengthen,
   subscribe, subsidize, supplement, supply, support,
   sweeten the kitty, take part in, tend, trend, turn, verge, vote,
   warp, work toward, yield