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