Clip vs magazine is not slang. Its the misapplication of two separate devices. Revolvers and automatics are both guns but are two very distinct types of guns for example.. On the other hand, water heaters and hot water heaters are both the same instrument operating in the same manner. If someone asked a plumber to install a hot water heater the plumber wouldn't install a garbage disposal in its place (unless they were from the Bronx and then all bets are off)