propagation / circulation / propagate / spread / circulate

propagate / become widespread / be popular / diffuse / becoming widespread / diffusion / spread / popularization

prevail / be the vogue / (fashion) be going on / be in now / prevalence / (fashion) be prevalent / be going on / be all the rage among / coming into fashion / be prevalent / (fashion) prevail / come into fashion / be popular / be the fashion

circulation / spread / be put into circulation / circulate

prevail / run current / spread / get about / be put in circulation / circulate

infiltrate / penetrate / permeate / spread / filter into / catch on

prevail / be rampant among [people] / domineer over / dominate

become impotent / lose strength / fall into decay / weaken

decline / decay (of civilization/morality)

decay / rot / fall into decay