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

propagation \prop`aga"tion\, n. l. propagatio: cf. f.
   propagation.
   1913 webster
   1. the act of propagating; continuance or multiplication of
      the kind by generation or successive production; as, the
      propagation of animals or plants.
      1913 webster

            there is not in nature any spontaneous generation,
            but all come by propagation.          --ray.
      1913 webster

   2. the spreading abroad, or extension, of anything;
      diffusion; dissemination; as, the propagation of sound;
      the propagation of the gospel. --bacon.
      1913 webster

[2] : WordNet (r) 2.0

propagation
     n 1: the spreading of something a belief or practice into new
          regions syn: extension
     2: the act of producing offspring or multiplying by such
        production syn: generation, multiplication
     3: the movement of a wave through a medium
see also:
extension generation multiplication 

[3] : Moby Thesaurus II by Grady Ward, 1.0

62 moby thesaurus words for "propagation":
   airing, attenuation, bandying, begetting, book, breeding,
   broadcast, broadcasting, bruiting, bruiting about, circulation,
   circumfusion, crossbreeding, diffraction, diffusion, dilution,
   dispensation, dispersal, dispersion, display, dissemination,
   dissipation, dissogeny, distribution, divergence, endogamy,
   engenderment, evaporation, evulgation, expansion, fragmentation,
   generation, inbreeding, issuance, issue, linebreeding,
   multiplication, outbreeding, peppering, periodical, printing,
   procreation, proliferation, promulgation, publication, publishing,
   radiation, scattering, scatterment, shotgun pattern, sowing,
   spattering, splay, spread, spreading, spreading abroad, sprinkling,
   strewing, telecasting, ventilation, volatilization, xenogamy

Propagation >> P Words
Propagation, definition of term: Propagation
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