Dyna Man is one of the three Robot Masters from the Mega Man computer game for DOS. His name is short for "Dynamite Man."
Dyna Man is a master of explosives, using his Nuclear Detonator weapon to quickly take out his opponents with dynamite sticks before they have a chance to get anywhere near him. He is weak to the Force Field, since his explosives can't get through the barrier and also cause him to short circuit, while detonating his explosives.
Mega Man PC/DOS - Dyna Man Stage
Dyna Man shares his name, as well as his powers of explosives, with the series Kagaku Sentai Dynaman, the seventh entry in the Super Sentai franchise. This is most likely unintentional, as the series aired several years before this game's release, and was never shown outside of Japan.