I was confused by what "Morning Star" meant because I hear people use this term differently. My understanding is it is a rigid spiked mace, whereas the thing with a spiked ball on a chain is a "flail."
In fact, Remo223's remark about hitting yourself in the knuckles reminds me of something I heard. I was told by a history buff friend that the iconic flail weapons (1-2 foot stick with chain and spiked ball on the end) are actually fictional. Little to no evidence exists they were used in medieval Europe. They did had long staff-like ones with cylindrical heads that were apparently modified agricultural tools, but not the spike-ball things. To make matters worse, in the 19th century there was this "fad" about medieval stuff (weapons, castles, torture implements) and a great many business-minded folk simply made things up or mutated existing items and published them in books or even made full size reproductions, labeling them as "historically accurate" when many of these items never existed. Some of the more functional "reproductions" actually sit to this day in our museums being passed off as real artifacts.