prop·a·ga·tion /ˌprɑpəˈgeʃən/ 名詞
1. The act of propagating; continuance or multiplication of the kind by generation or successive production; as, the propagation of animals or plants.
There is not in nature any spontaneous generation, but all come by propagation. --Ray.
2. The spreading abroad, or extension, of anything; diffusion; dissemination; as, the propagation of sound; the propagation of the gospel.
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