moment [LME] The Latin word momentum is the source of our words moment and momentum [OE]. Its root is movere, ‘to move’. At the end of a bullfight the matador faces the bull and prepares to make the final sword thrust. In Spanish this is la hora de la verdad, translated into English as the moment of truth. The first recorded use was by the writer Ernest Hemingway in his 1932 book Death in the Afternoon.