The Collaborative International Dictionary of English v.0.48:

Propagate \Prop"a*gate\, v. i.
   To have young or issue; to be produced or multiplied by
   generation, or by new shoots or plants; as, rabbits propagate
   rapidly.
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         No need that thou
         Should'st propagate, already infinite.   --Milton.
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The Collaborative International Dictionary of English v.0.48:

Propagate \Prop"a*gate\, v. t. [imp. & p. p. Propagated; p.
   pr. & vb. n. Propagating.] [L. propagatus, p. p. of
   propagare to propagate, akin to propages, propago, a layer of
   a plant, slip, shoot. See Pro-, and cf. Pact, Prop,
   Prune, v. t.]
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   1. To cause to continue or multiply by generation, or
      successive production; -- applied to animals and plants;
      as, to propagate a breed of horses or sheep; to propagate
      a species of fruit tree.
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   2. To cause to spread to extend; to impel or continue forward
      in space; as, to propagate sound or light.
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   3. To spread from person to person; to extend the knowledge
      of; to originate and spread; to carry from place to place;
      to disseminate; as, to propagate a story or report; to
      propagate the Christian religion.
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            The infection was propagated insensibly. --De Foe.
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   4. To multiply; to increase. [Obs.]
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            Griefs of mine own lie heavy in my breast,
            Which thou wilt propagate.            --Shak.
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   5. To generate; to produce.
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            Motion propagated motion, and life threw off life.
                                                  --De Quincey.
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   Syn: To multiply; continue; increase; spread; diffuse;
        disseminate; promote.
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WordNet (r) 3.0 (2006):

propagate
    v 1: transmit from one generation to the next; "propagate these
         characteristics"
    2: travel through the air; "sound and light propagate in this
       medium"
    3: transmit; "propagate sound or light through air"
    4: become distributed or widespread; "the infection spread";
       "Optimism spread among the population" [syn: spread,
       propagate]
    5: transmit or cause to broaden or spread; "This great
       civilization was propagated throughout the land"
    6: cause to become widely known; "spread information";
       "circulate a rumor"; "broadcast the news" [syn: circulate,
       circularize, circularise, distribute, disseminate,
       propagate, broadcast, spread, diffuse, disperse,
       pass around]
    7: cause to propagate, as by grafting or layering
    8: multiply sexually or asexually

Moby Thesaurus II by Grady Ward, 1.0:

67 Moby Thesaurus words for "propagate":
   bear, beget, bestrew, breed, breed true, bring forth, broadcast,
   bruit about, circulate, circumfuse, copulate, crossbreed,
   cultivate, deal out, deliver, develop, diffract, diffuse, dispense,
   disperse, dispread, disseminate, distribute, diverge, engender,
   fan out, father, generate, get, grow, herald, inbreed, increase,
   issue, make known, make love, mother, multiply, noise abroad,
   outbreed, overscatter, oversow, overspread, proclaim, procreate,
   produce, proliferate, promote, promulgate, propagandize, publicize,
   publish, radiate, raise, reproduce, reproduce in kind, retail,
   scatter, sire, sow, sow broadcast, splay, spread, spread out,
   strew, transmit, utter