意味着一年比一年高、年年高升、年年丰收。 年糕(rice cake (made of glutinous rice flour)in chinese voice it sounds the same voice with 年高. 年高 here means your life and work and your fortune will be better and better year by year. so this make a idom. if you eat the rice cake ,you will be better year by year. all because their chinese pronunciation are same。