1. Day after day means "day after day". Deep meaning means "regarding the day as continuous, which means long time". \ x0d \ x0d \ For example, day after day passed and no news came. \ x0d \ (days go by and there is still no news) \x0d\\x0d\2. Day after day means "day after day", and the deeper meaning means "treating every day as an independent individual". Much like word change, turn. \ x0d \ x0d \ For example, my husband is getting older day by day. \x0d\ (My husband is getting better every day) \ x0d \ This sentence contains the meaning of "getting better gradually and finally recovering completely".