flash [ME] We think of flash in terms of fire and light, but in the Middle Ages it originally meant ‘splash water about’, and like plash [OE] and splash [M18th] probably came from the sound of the word. The association with fire may have developed from the resemblance of the word to flame (see flagrant). The idea of ‘ostentatious stylishness or display of wealth’ goes back to the 17th century, with Flash Harry dating from at least the 1950s. When calling a sudden, brief success a flash in the pan [E18th] we are referring to early firearms. Sometimes the gunpowder would burn fiercely but ineffectually in the ‘pan’, the part that held the priming charge, without igniting the main charge. The result was a flash and some smoke, but the gun did not fire.